¶ 1. The petitioner, State of Wisconsin, seeks review of a published court of appeals decision that reversed Media DeLao's convictions and remanded her case for a new trial.1 The State argues that the court of appeals erred in determining that the State violated its discovery obligations when it failed to disclose before trial oral statements made by DeLao. In addition, the State asserts that even if it violated its discovery obligations, it did so for good cause, and DeLao was not prejudiced by the admission of her statements.
¶ 2. We determine that the State violated its discovery obligations under the criminal discovery statute, Wis. Stat. § 971.23(l)(b) (1999-2000),2 when it failed to disclose DeLao's oral statements before her trial began. In addition, we conclude that the State failed to show good cause for its violation and that DeLao was preju*296diced by the subsequent admission of her statements. Accordingly, we affirm the court of appeals decision.3
HH
¶ 3. DeLao's boyfriend, Desmond Stalsberg, was a suspect in a May 31, 1999 robbery of a grocery store, along with another man, John Sabala. Detective James Prioletta of the City of Racine Police Department carried out the follow-up investigation of the robbery.
¶ 4. One week after the robbery, Stalsberg and Sabala got into a fight while at DeLao's house. Stalsberg fired shots at Sabala as Sabala fled the house. Investigator Doug Chaussee of the Mount Pleasant Police Department was the central investigator assigned to the shooting, and he interviewed DeLao at her home on the day of the incident. She initially denied involvement with the shooting or knowledge of Stalsberg's whereabouts. However, when Chaussee interviewed her again that night, she admitted that she had been present during the shooting and that Stalsberg had directed her to help him clean up the crime scene. She told Chaussee that she was afraid and that Stalsberg was "acting crazy."
¶ 5. The State filed a criminal complaint against DeLao alleging, among other counts, that she ob*297structed an officer and harbored or aided a felon.4 The charges against her were connected with her conduct after the shooting. The State alleged that she misled the police and cleaned up or sanitized the crime scene.
¶ 6. Sometime after Investigator Chaussee interviewed DeLao about the shooting, he told Detective Prioletta that DeLao may have information about the robbery. Prioletta interviewed DeLao on June 28, 1999, while she was in custody, and he took notes on her oral statements.5 The focus of his inquiry was on the robbery investigation.
¶ 7. Prior to trial and pursuant to § 971.23(l)(b), DeLao filed a discovery demand requesting that the State provide her with written summaries of any oral statements she made. Her trial was to begin on Tuesday, July 27, 1999. On Sunday, July 25, Investigator Chaussee spoke with Detective Prioletta, who informed Chaussee of DeLao's statements, which indicated that she was not afraid of Stalsberg.
¶ 8. The trial proceeded as scheduled, and during DeLao's opening statement, her attorney told the jury that DeLao would testify and explain that she acted out of fear of Stalsberg. Her attorney said that DeLao's case could be summed up in one word, "survival," and *298concluded the opening statement with an acknowledgement that DeLao lied to police but did what she did because she was afraid.
¶ 9. After the State rested its case in chief on the second day of trial, the prosecutor informed the circuit court of DeLao's statements to Detective Prioletta. Indicating that the State intended to use the statements to impeach DeLao, the prosecutor explained that although Investigator Chaussee knew of DeLao's statements before the trial began, the prosecutor had not learned of them until that morning.
¶ 10. DeLao objected to the admissibility of the statements, arguing that the State violated the criminal discovery statute. After the circuit court overruled her objection, she moved for a mistrial. Her counsel explained that DeLao's decision to testify had depended on the information the State provided before trial. Because DeLao's theory of defense was coercion, it was her position that it would be prejudicial to allow the State to cross-examine her based on undisclosed statements that indicated she was not afraid of Stalsberg. At the same time, counsel noted, if DeLao failed to take the stand contrary to what the defense promised, "then I have basically lied to the jury."
¶ 11. Denying DeLao's motion for a mistrial, the circuit court disagreed that the statements would be prejudicial, and the State proceeded to cross-examine DeLao using the statements. After DeLao testified, the State called Detective Prioletta to the witness stand as part of its rebuttal case. He testified that when he spoke with DeLao, she never expressed any fear of Stalsberg.
¶ 12. In its closing argument, the State maintained that DeLao's statements to Detective Prioletta were inconsistent with her coercion defense. The jury found DeLao guilty, and she appealed.
*299¶ 13. Reversing DeLao’s conviction, the court of appeals determined that the State violated its discovery obligations. In addition, the court determined that the State failed to show good cause for its violation. Concluding that the subsequent admission of DeLao's statements required a new trial, the court reasoned:
DeLao was caught on the horns of a dilemma, placed in that position by the State-either she must testify and accept the consequences of impeachment, or break her promise to the jury that she would testify and accept the consequences of her broken promise.
State v. DeLao, 2001 WI App 132, ¶ 28, 246 Wis. 2d 304, 629 N.W.2d 825. The State petitioned this court for review.
II
¶ 14. The State asks that we address several issues in resolving this case. The first question we address is whether the court of appeals correctly concluded that the State violated its discovery obligations. This requires the interpretation and application of § 971.23(1)03) to a given set of facts. It presents a question of law subject to independent appellate review. See State ex rel. Angela M.W. v. Kruzicki, 209 Wis. 2d 112, 121, 561 N.W.2d 729 (1997).
¶ 15. Because we conclude that the State violated § 971.23(l)(b), we must also determine whether the State has shown good cause for the violation, and if not, whether DeLao was prejudiced by the admission of her statements. These are also questions of law subject to independent appellate review. See State v. Messelt, 185 *300Wis. 2d 254, 275, 518 N.W.2d 232 (1994) (prejudicial error); State v. Martinez, 166 Wis. 2d 250, 259, 479 N.W.2d 224 (Ct. App. 1991) (good cause).
pH I — l HH
¶ 16. Our interpretation and application of § 971.23(l)(b) involves an inquiry into (1) the scope of the prosecutor's obligation under the statute to make herself aware of evidence against the accused and (2) the meaning of the statutory language, "plans to use in the course of the trial."
¶ 17. Section 971.23, entitled "Discovery and inspection" largely controls the scope of the State's statutory discovery obligations in criminal cases. The portion of the statute that is the focus of our inquiry is subsection (1)(b), which reads:
(1) WHAT A DISTRICT ATTORNEY MUST DISCLOSE TO A DEFENDANT. Upon demand, the district attorney shall, within a reasonable time before trial, disclose to the defendant or his or her attorney and permit the defendant or his or her attorney to inspect and copy or photograph all of the following materials and information, if it is within the possession, custody or control of the state:
(b) A written summary of all oral statements of the defendant which the district attorney plans to use in the course of the trial and the names of witnesses to the defendant's oral statements.
¶ 18. The statute requires the State to provide, within a reasonable time before trial begins, a written summary of the defendant's oral statements that the prosecutor plans to use at trial. Even though the State *301did not disclose DeLao's statements to Detective Prio-letta before her trial began, the State asserts that it complied with § 971.23(l)(b) because the prosecutor could not have planned to use the statements until she knew of them. We reject the State's analysis because it does not comport with the requirements of the statute.
¶ 19. Section 971.23 has been revised over the years, but many of the provisions have remained the same since its creation as three separate statutory sections in the comprehensive 1969 redrafting of the criminal procedure statutes. Jones v. State, 69 Wis. 2d 337, 348, 230 N.W.2d 677 (1975); see also Wis. Stat. § 971.23, and compare with Wis. Stat. §§ 971.23-25 (1993-94), and with Wis. Stat. §§ 971.23-25 (1971). Most recently, 1995 Wis. Act 387 repealed, recreated, and renumbered the discovery provisions found in the present version of § 971.23.
¶ 20. Some of the provisions that were new or revised under 1995 Wis. Act 387 were intended to expand the discovery and disclosure requirements that apply to both the State and the defendant. However, the substance of many of the provisions, including what is now subsection (1)(b), has remained essentially unchanged. See 1995 Wis. Act. 387; 1995 A.B. 721.
¶ 21. Under § 971.23, the State's discovery obligations may extend to information in the possession of law enforcement agencies but not personally known to the prosecutor. Jones, 69 Wis. 2d at 349; State v. Maass, 178 Wis. 2d 63, 69, 502 N.W.2d 913 (Ct. App. 1993). Put another way, under certain circumstances, the knowledge of law enforcement officers may be imputed to the prosecutor.
¶ 22. In Jones, 69 Wis. 2d at 348-49, this court interpreted the discovery statutes in light of Wold v. *302State, 57 Wis. 2d 344, 204 N.W.2d 482 (1973). Wold, in turn, adopted the American Bar Association (ABA) Standards Relating to the Prosecution Function and the Defense Function: "The test of whether evidence should be disclosed is not whether in fact the prosecutor knows of its existence but, rather, whether by the exercise of due diligence [the prosecutor] should have discovered it." Jones, 69 Wis. 2d at 349 (citing Wold, 57 Wis. 2d at 349-50). The court further explained:
The prosecuting attorney's obligations under this section [of the ABA Standards] extend to material and information in the possession or control of members of his staff and of any others who have participated in the investigation or evaluation of the case and who either regularly report or with reference to the particular case have reported to his office.
Id. In Wold, the court was not interpreting the criminal discovery statutes. Instead, the State's discovery obligation was predicated on the prosecutor's agreement to produce. See 57 Wis. 2d at 347. Nonetheless, Jones and subsequent cases citing Wold have interpreted the discovery statutes to incorporate Wold's rationale, including its reliance on the ABA Standards.
¶ 23. In Martinez, the court of appeals stated:
For purposes of the criminal discovery statutes, we view an investigative police agency which holds relevant evidence as an arm of the prosecution. In most criminal cases, the evidence against the accused is garnered, stored and controlled by the investigating police agency. Depending upon local practice, many courts and district attorneys entrust the custody and control of such material to the police even after it has been elevated to formal evidentiary status in a criminal proceeding.
166 Wis. 2d at 260; see also State v. Sturgeon, 231 Wis. 2d 487, 499, 605 N.W.2d 589 (Ct. App. 1999); Maass, 178
*303Wis. 2d at 69-70 (citing Wold, 57 Wis. 2d at 349-50). The court in Maass determined that the ABA Standards were "codified in sec. 971.23." 178 Wis. 2d at 70. In short, the threads of Wold and Jones have become tightly woven into the fabric of criminal discovery in Wisconsin.
¶ 24. The prosecutor's duty to obtain information from investigative agencies is not, however, limitless. For example, due diligence does not require that the prosecutor "consult every law enforcement officer who conceivably could have information respecting a case." Maass, 178 Wis. 2d at 71. This limitation is consistent with the ABA Standards and in keeping with the principles in Jones and Wold. The State is charged with knowledge of material and information in the possession or control of others who have participated in the investigation or evaluation of ttíe case and who either regularly report or with reference to the particular case have reported to the prosecutor's office. Jones, 69 Wis. 2d at 349; Wold, 57 Wis. 2d at 349 n.4.
¶ 25. We turn next to examine the meaning of the language in § 971.23(l)(b) limiting the State's obligation to disclose a defendant's oral statements to those ■that it "plans to use in the course of the trial." The State maintains that the phrase "plans to use" embodies a subjective component. According to the State, the prosecutor in DeLao's case could not have planned to use DeLao's statements before DeLao's trial began because a prosecutor cannot plan to use what the prosecutor does not actually know. DeLao asserts, in contrast to the State, that the phrase "plans to use" in § 971.23(l)(b) embodies an objective standard. We agree with DeLao that the standard is necessarily objective.
*304¶ 26. In advancing a subjective standard, the State relies on State v. Larsen, 141 Wis. 2d 412, 415 N.W.2d 535 (Ct. App. 1987). The central issue in Larsen was whether the defendant was entitled to a discretionary reversal under Wis. Stat. § 752.35.6 Id. at 416. The defendant advanced a number of arguments in support of his assertion that justice miscarried. One of his several arguments was that he was denied a fair trial because the state failed to comply with § 971.23(1), despite the fact that it had disclosed his statements before the trial began.
¶ 27. The court of appeals devoted only one paragraph of analysis to this argument. It noted that the district attorney explained that he did not intend to use the statements until the defendant filed his notice of alibi. Larsen, 141 Wis. 2d at 425. The notice of alibi was filed two weeks before trial and the statements were provided to the defendant one week before trial. Id. at 417, 425. In determining that the prosecutor's failure to disclose the statements sooner did not deny the defendant a fair trial, the court referenced the time at which the prosecutor actually decided to use the defendant's statements. See id. at 425-26.
¶ 28. We do not view Larsen as dispositive of the question before us. The court in Larsen was addressing a pretrial disclosure. In the case before us, the disclosure came after the trial began and after the defense committed to a trial strategy based on the information it had at the beginning of trial. The Larsen court *305concluded that given the circumstances of the pretrial disclosure, it could not conclude that justice had miscarried.
¶ 29. More importantly, Larsen is not dispositive because the court of appeals was not addressing the scope of the meaning of "plans to use" — the issue before us. Rather, its discussion of the prosecutor's decision was part of its larger determination that the defendant was not entitled to a discretionary reversal in the interest of justice.
¶ 30. Thus, the court of appeals in Larsen arguably assumed that § 971.23(1) embodied a subjective standard, without engaging in any construction of the statute as we do today. We interpret the phrase "plans to use" to necessarily embody an objective standard: what a reasonable prosecutor should have known and would have done under the circumstances of the case. An objective standard is consistent with the due diligence-imputed knowledge rule under Wold and its progeny.
¶ 31. In contrast, a subjective standard would be difficult if not impossible to reconcile with the rule that a prosecutor is responsible for exercising due diligence in obtaining statements of which she does not know. The State's theory in this case illustrates this problem. Under that theory, the State could escape its obligation to disclose under § 971.23(l)(b) in every case where the prosecutor failed to exercise due diligence by asserting that the prosecutor, not knowing of the evidence, could not have planned to use it.
¶ 32. Likewise, a subjective standard would create an uncomfortably large opening through the door to prosecutorial sandbagging and discovery abuse. Al*306though there is no affirmative evidence of gamesmanship in this case, a subjective standard would invite it in future cases. Moreover, a subjective standard would spawn cases requiring irksome inquiries into the intent of the prosecutor. Thus, the phrase "plans to use" in the statute necessarily embodies an objective standard.
¶ 33. Having examined the scope of the prosecutor's obligation under the statute and the statutory phrase "plans to use in the course of the trial," we turn to an application of § 971.23(l)(b) to the facts of this case. The issue becomes whether a reasonable prosecutor, exercising due diligence, should have known of DeLao's statements before trial, and if so, whether a reasonable prosecutor would have planned to use them in the course of trial. Given all the facts here, we conclude that a reasonable prosecutor should have known of the statements and would have planned to use them.
¶ 34. Investigator Chaussee, who knew of DeLao's statements before trial after speaking with Detective Prioletta, was a key actor in the State's case against DeLao. Over DeLao's objection, Chaussee was not sequestered like the other witnesses. He was allowed to remain with the prosecutor throughout the trial as the State's representative. At the trial conference held prior to the entrance of the jury pool, the prosecutor explained, "Your Honor, Investigator Chaussee was the central investigator that ties all of the ends together."
¶ 35. As the court of appeals concluded, the investigation of the robbery and the investigation of the shooting were "hopelessly intertwined" with respect to DeLao. The two investigations overlapped substantially both in time and in the cast of characters involved. The robbery and the shooting occurred a week apart, and *307DeLao's testimony revealed that she had a significant history with Stalsberg and Sabala.
¶ 36. Detective Prioletta and Investigator Chaus-see were in contact about their investigations. When the discovery issue arose at trial, and after the parties and the court examined Prioletta's report, DeLao's attorney commented:
Your honor, in this report given to me today, Investigator Chaussee's name is pretty — is made pretty frequent in this report. Investigator Chaussee was the one that told Investigator Prioletta that Ms. DeLao may have information about these robberies.
¶ 37. One of the State's arguments in support of its failure to disclose is an assertion that DeLao's statements to Detective Prioletta gained relevance "only when the 'acting out of fear' theory of the defense was revealed during defense counsel's opening statement." In contrast, DeLao maintains that her defense was apparent from the beginning. We agree with the State that the potential relevance of evidence goes to the question of what a reasonable prosecutor would plan to use. However, the State's characterization of DeLao's theory of defense as materializing on the day her trial began is not supported by the facts. DeLao's assessment of the record is more accurate, and the relevance of her statements related not just to the State's ability to rebut her testimony by impeaching her but to her entire defense.
¶ 38. At oral argument in this court, DeLao's counsel advanced: "From the very first night of this crime, Investigator Chaussee interviewed Ms. DeLao . . . she said in her very first statement to him, 'I did what I did because Desmond Stalsberg was acting crazy and I was afraid of him.'"
*308¶ 39. Although Investigator Chaussee's report detailing his conversations with DeLao on the night of the shooting does not appear in the record, the comments made by DeLao's trial attorney during opening statement, on the record, support this contention. Her attorney asserted, without objection, that on the night of the shooting, DeLao admitted to Chaussee that she previously lied to the police. DeLao's attorney stated: "... and she told him why she lied to the police officer. She said I was afraid, Desmond was acting crazy that day."
¶ 40. Even at DeLao's initial appearance, her attorney's comments suggested what her defense would be. DeLao's attorney explained:
If what is in the criminal complaint is to be believed, what it sounds like is that [DeLao] . . . basically, did not know what to do. This other individual is shooting at someone, out of control, and Ms. DeLao probably didn't ■ know what to do. She was told to clean up the porch and she picked up some gun casings and gave it to the person because there were children in the area.
¶ 41. Again, at DeLao's preliminary hearing, which took place one and one half months before her trial, DeLao's "acting out of fear" defense was raised.7 DeLao's attorney questioned Investigator Chaussee as to whether DeLao indicated any fear of Stalsberg:
Q. And that she — Did she indicate to you that she was afraid at the point that she was picking up those shells?
*309A. She said she was told to pick them up by Desmond.
Q. And did she indicate that he had a gun at the time he was telling her to do it?
A. He was in possession of a firearm, that's correct.
Q. Did she indicate she was afraid at the time she was doing it?
A. I don't recall her specifically saying that.
Q. Did she indicate to you when you talked with her that basically all she wanted to do was to get Desmond out of her house?
¶ 42. On redirect, the assistant district attorney representing the State also asked Investigator Chaus-see whether DeLao told him she feared Stalsberg, to which he replied that he did not recall. Finally, on re-cross of Chaussee, the sole area of inquiry focused on DeLao's fear:
Q. So are you indicating that you just simply don't recollect or are you saying that you just don't remember whether or not she was in fear for her life? She told you she was in fear for her life or that wasn't said?
A. I don't recall it being said.
¶ 43. In short, it seems that from the beginning of this case, DeLao maintained that she did what she did because she was afraid of Stalsberg. From the outset, she admitted that she removed evidence from the crime scene — the basis of the harboring or aiding a felon charge. She acknowledged that she initially lied to the police — the basis of the obstructing charge. Her response to these charges rested not on denying she committed the acts, but rather on a defense that she *310committed them out of fear. Thus, the record does not support the State's assertion that DeLao's "acting out of fear" theory of defense became apparent only after her trial began.
¶ 44. Also important to our analysis is the nature of the evidence at issue in this case. This evidence consisted of DeLao's own statements, made while she was in custody, to a police officer who was dispatched to interview her by the lead investigator in the case for which she was charged. While we do not suggest that a reasonable prosecutor would know of and plan to use any and all statements by a defendant, these statements were not just any statements.
¶ 45. The State also relies on Maass, in which three days before the defendant's trial, a police officer came forward to the prosecutor with incriminating statements the defendant had made to him. 178 Wis. 2d at 65. The defendant, Maass, moved to exclude any testimony by the officer, and the circuit court granted the motion. Id. at 66. The court of appeals, however, determined that the State did not violate § 971.23. Id. at 73. It noted that the officer did not participate in the investigation or evaluation of Maass's case or regularly report to the district attorney. Id. at 72. The court reasoned that the officer's "failure to appreciate the significance of Maass's inculpatory statements and his last-minute disclosure of those statements to the district attorney should not deprive the state of this valuable evidence." Id.
¶ 46. The facts of Maass are distinguishable from DeLao's case in two important ways. First, the prosecutor in Maass notified the defendant of his statements before trial began. 178 Wis. 2d at 65. Second, there was no indication that the officer's knowledge in Maass was the result of an investigation that was closely inter*311twined with the investigation that resulted in Maass's conviction. The different results in Maass's and DeLao's cases serve to illustrate that the question of whether the prosecutor has exercised due diligence, though ultimately a question of law, will be highly fact-dependent.
¶ 47. Given the coextensive character of the two investigations and Investigator Chaussee's pivotal role in DeLao's case, we determine that a reasonable prosecutor should have known of DeLao's statements before trial began. Chaussee knew of the statements before trial began, and under the facts of this case, the State is charged with Chaussee's knowledge of those statements.8 In addition, we determine that given all the circumstances, including the fact that DeLao maintained from the outset that she acted out of fear, a reasonable prosecutor who was aware of DeLao's statements would have planned to use them in the course of trial. Therefore, the State violated § 971.23(l)(b) when it failed to disclose the statements before DeLao's trial began.
¶ 48. We next address the State's assertion that the court of appeals decision incorrectly expanded the *312State's discovery obligations to include any information requested by a defendant, regardless of whether the information is discoverable under § 971.23. The bulk of the court of appeals' reasoning in support of its determination that the State violated its discovery obligations consists of a discussion of the imputed knowledge rule of Jones and Martinez. However, paragraph 17 of the opinion reads as follows:
DeLao requested, pursuant to Wis. Stat. § 971.23(l)(b), "a written summary of any oral, written or recorded statements of the defendant, but not limited to those statements which the state intends to use in the course of the trial." (Emphasis added.) Thus, DeLao asked for all statements, not just the ones the State intended to use at trial. The statements in question fell within the purview of her discovery demand. The State made no objection to DeLao's discovery demand as overbroad or beyond the scope of § 971.23(l)(b).
DeLao, 2001 WI App 132, ¶ 17. Thus, the State reads the court of appeals opinion to give import to the State's failure to object to DeLao's discovery demand.
¶ 49. As a general rule, the discovery to which a criminal defendant is entitled is limited to constitutional and statutory requirements. See State v. O'Connor, 77 Wis. 2d 261, 280 n.7, 252 N.W.2d 671 (1977). Thus, as the State asserts, this court has stated that the discovery statute "controls as to the rights of a defendant as to discovery and the procedures to be followed in enforcing such rights." State v. Calhoun, 67 Wis. 2d 204, 217, 226 N.W.2d 504 (1975).
¶ 50. Although we agree with the court of appeals that the State violated its discovery obligations, those *313obligations arose under § 971.23 and not as a result of the State's failure to object to DeLao's discovery request. Indeed, at oral argument DeLao unequivocally asserted that throughout this case she has relied not on the State's failure to object but on the statute, arguing that her statements fall within its purview. Accordingly, we reject the court of appeals' discussion to the extent it can be read to suggest that absent an objection, the State is required to provide materials requested by the defendant that fall outside the scope of statutory or constitutional discovery requirements.
IV
¶ 51. Our conclusion that the State violated its discovery obligations under § 971.23(l)(b) does not end our inquiry. The State argues that it had good cause for failing to disclose. Absent a showing of good cause, the evidence the State failed to disclose must be excluded. Wis. Stat. § 971.23(7m); State v. Wild, 146 Wis. 2d 18, 27, 429 N.W.2d 105 (Ct. App. 1988).9 However, if the State can show good cause for its failure to disclose, the circuit court may exclude the evidence or may grant other relief such as a recess or continuance. Section 971.23(7m); Wild, 146 Wis. 2d at 27. The burden of proving good cause rests on the State. Martinez, 166 Wis. 2d at 257.
¶ 52. The State argues it had good cause for two reasons: (1) it acted in good faith, and (2) even if the prosecutor had known of the statements, she would *314have had no reason to believe that they were relevant to DeLao's case. We have already disposed of the State's second argument by determining that a reasonable prosecutor would have planned to use the statements at DeLao's trial. Having concluded that "plans to use" in § 971.23(l)(b) necessarily embodies an objective standard, we decline to apply a subjective analysis for purposes of good cause. This would create an exception that swallows the rule.
¶ 53. That leaves good faith. Certainly, good faith is an important factor in a determination of good cause. See Martinez, 166 Wis. 2d at 259; Wild, 146 Wis. 2d at 28. However, it is not by itself dispositive. Martinez, 166 Wis. 2d at 259. In any event, we conclude that the State's assertion that it acted in good faith is insufficient to show good cause for its failure to disclose. A closer look at the Martinez case illustrates our conclusion.
¶ 54. In Martinez, the evidence at issue was a surveillance tape recording of the defendant that incriminated her in a drug deal. Although the State attempted to make the tape available to the defendant in accordance with the defendant's discovery request, the attempt failed and the tape was lost. Martinez, 166 Wis: 2d at 253-55. The State conceded that it had "goofed up," but the circuit court allowed police officers who had conducted the surveillance to testify as to their recollections of what they heard. Id. at 254, 256. The court of appeals reversed with this explanation:
The trial court concluded that the state's actions were "simply negligence" and not done in bad faith. We disagree that the facts permitted this conclusion. Instead, the limited facts offered by the state allowed for a host of speculative (not reasonable) inferences as to *315the state's conduct — good faith, negligence, recklessness, intentional conduct, or bad faith. This points to the fundamental problem — the failure of the state to meet its burden under the statute.
Id. at 258 (footnote omitted). The court added that "[e]ven if the facts could be read to support the trial court's 'negligence/no bad faith' conclusion, this still begs the question of 'good cause' under the statute." Id. The court of appeals refused to hold that "negligence or lack of bad faith constitutes 'good cause' as a matter of law." Id.
¶ 55. Thus, as did the court of appeals in Martinez, we conclude that even if the State acted in good faith, it failed to show good cause for its failure to disclose. The State emphasizes that there is no indication that it engaged in sandbagging or otherwise acted in bad faith. However, the State's assertions miss the mark because it has the burden to provide some explanation other than good faith.
¶ 56. Finally, in asserting it has shown good cause, the State relies on Tucker v. State, 84 Wis. 2d 630, 267 N.W.2d 630 (1978). In Tucker, the State failed to supply a defendant with the name of an alibi rebuttal witness who was able to place the defendant running from the scene of the crime. Id. at 633-34. Another witness whose name the State had provided also placed Tucker at the scene of the crime. Id. The defendant moved for a mistrial, but the circuit court denied the motion. Id. at 635. After determining on appeal that the State had committed a discovery violation, this court concluded that the defendant suffered no prejudice and that a new trial was unnecessary. See id. at 639, 641. In so concluding, the court noted that the prosecutor did not know that the rebuttal witness would identify the defendant until one-half hour before trial and indicated *316that this "may have been good cause for granting a recess or continuance." Id. at 640.
¶ 57. We are not persuaded that this language in Tucker means that the State has shown good cause in DeLao's case. The court in Tucker did not analyze the question of whether the prosecutor's failure to know of the witness's statement was or was not excusable for good cause, and the facts recited in the case do not suggest an answer.
¶ 58. Under Martinez, some explanation in addition to good faith is necessary, and the State has been unable to provide that explanation here. As we have already determined using the objective standard embodied in § 971.23(l)(b), the fact that the prosecutor in DeLao's case did not actually know of the evidence is no explanation at all. In short, the State has failed to demonstrate good cause for its violation of the discovery statute. Therefore, DeLao's statements should have been excluded.
V
¶ 59. Having determined that DeLao's statements should have been excluded because the State violated § 971.23(l)(b) without good cause, we address the question of whether the admission of DeLao's statements was prejudicial to her case, thus requiring a new trial. The State asserts there is no prejudice here.10
*317¶ 60. When evidence that should have been excluded under § 971.23 is not excluded, the defendant is not automatically entitled to a new trial. State v. Ruiz, 118 Wis. 2d 177, 199-200, 347 N.W.2d 352 (1984); Kutchera v. State, 69 Wis. 2d 534, 544-45, 230 N.W.2d 750 (1975). If the defendant is to receive a new trial, the improper admission of the evidence must be prejudicial. Ruiz, 118 Wis. 2d at 199. "The penalty for the breach of disclosure should fit the nature of the proffered evidence and remove any harmful effect on the defendant." Kutchera, 69 Wis. 2d at 542-43 (quoting Wold, 57 Wis. 2d at 351).
¶ 61. We agree with the court of appeals that the State's failure to comply with § 971.23 placed DeLao on the horns of a dilemma from which no judicial remedy other than a new trial could save her. DeLao's own statements were used against her, and those statements were relevant not just as impeachment evidence but as relating to her entire defense. Thus, the State's discovery violation went to the core of her trial preparation and strategy.
¶ 62. By the time the State disclosed DeLao's statements, she had committed to a defense strategy *318that was inconsistent with the statements. When the circuit court determined the statements could come in, DeLao had no choice but to break her promise to the jury or take the stand and subject herself to impeachment by evidence that she had not anticipated when she made the promise.
¶ 63. It is particularly significant that the disclosure was in the midst of trial. The primary focus of § 971.23(l)(b) is on disclosure before trial. Indeed, that is the very nature of discovery. "If there is to be pretrial discovery, broad or limited, in criminal cases, defense counsel should be able to rely upon evidence as disclosed by the state; otherwise, the purpose of discovery is frustrated and more injustice is done than if no discovery were allowed." Wold, 57 Wis. 2d at 351.
¶ 64. We note that two purposes of criminal discovery are to ensure fair trials and to encourage defendants to enter pleas after learning the strength of the State's case. Irby v. State, 60 Wis. 2d 311, 320, 210 N.W.2d 755 (1973); State v. Maday, 179 Wis. 2d 346, 353, 507 N.W.2d 365 (Ct. App. 1993). Both purposes are thwarted when the State fails to provide the information required of it before trial begins.
¶ 65. Here, the State's discovery violation undermined the essence of discovery. It placed DeLao on the horns of a dilemma and prejudiced her case. She must have the opportunity to choose a strategy and prepare for trial in light of all the evidence that shduld have been provided her. Therefore, we determine, as did the court of appeals, that she is entitled to a new trial.11
*319VI
¶ 66. In sum, we conclude that the State violated § 971.23(l)(b) when it failed to disclose DeLao's oral statements before her trial began. In addition, we determine that the State failed to show good cause for its violation. Finally, we conclude that DeLao was prejudiced by the admission of her statements. Accordingly, we affirm the court of appeals decision reversing DeLao's conviction and remanding her case for a new trial.
By the Court. — The decision of the court of appeals is affirmed.
See State v. DeLao, 2001 WI App 132, 246 Wis. 2d 304, 629 N.W.2d 825 (reversing and remanding a judgment and an order of the Circuit Court for Racine County, Dennis J. Flynn, Judge. DeLao was convicted for obstructing an officer, harboring or aiding a felon, and possession of a short-barreled shotgun).
All subsequent references to the Wisconsin Statutes are to the 1999-2000 version unless otherwise indicated.
DeLao asks that we address two other issues not decided by the court of appeals. She asserts that the circuit court erred in (1) allowing the State to amend the information after the close of evidence and (2) failing to make a complete record of events surrounding jury deliberations. Because we agree with the court of appeals that DeLao is entitled to a new trial based upon the State's discovery violation, we need not address these two issues.
DeLao was also charged with two counts of possession of a short-barreled shotgun or rifle and possession of drug paraphernalia. She was acquitted of the harboring or aiding count as originally charged under Wis. Stat. § 946.47(l)(b), but at trial the State amended the information to include a harboring or aiding charge under § 946.47(1)(a) for which she was convicted.
Detective Prioletta testified that he interviewed DeLao on June 28, but the court of appeals decision states the date as June 29. The exact date is unimportant for purposes of our decision.
Wisconsin Stat. § 752.35 states in part:
Discretionary reversal. In an appeal to the court of appeals, if it appears from the record that the real controversy has not been fully tried, or that it is probable that justice has for any reason miscarried, the court may reverse the judgment or order appealed from.
The dissent notes that Judge Flynn, who presided over DeLao's trial, determined that the parties presented him with nothing indicating that the State was aware of any theory of defense before DeLao's opening statement. See dissent at ¶ 124. However, we note that Judge Flynn did not preside at DeLao's preliminary hearing or initial appearance.
The dissent's emphasis on City of Racine Detective Prioletta's role in the investigation clouds the focus of the majority opinion. It is Investigator Chaussee who participated in the investigation and evaluation of DeLao's case and reported to the district attorney with respect to her case. Accordingly, it is Chaussee's knowledge, not that of Prioletta, which is imputed to the district attorney. Thus, contrary to what the dissent suggests, our decision does not stand for the proposition that the discovery statute imposes on the district attorney "an undifferentiated duty to consult every law enforcement officer who conceivably could have information respecting a case under investigation." Dissent at ¶ 79 (citing State v. Maass, 178 Wis. 2d 63, 71, 502 N.W.2d 913 (Ct. App. 1993)).
This court has criticized the decision in State v. Wild, 146 Wis. 2d 18, 429 N.W.2d 105 (Ct. App. 1988), on an unrelated point. See State v. Eichman, 155 Wis. 2d 552, 562-63, 456 N.W.2d 143 (1990).
The court of appeals did not employ a harmless error analysis in deciding that DeLao was entitled to a new trial. Neither DeLao nor the State briefed or argued the question of whether a new trial is warranted in the express terms of a harmless error analysis. Nevertheless, the dissent is correct that some of the case law addressing the proper remedy for a discovery violation refers to harmless error. See State v. Ruiz, *317118 Wis. 2d 177, 198-99, 347 N.W.2d 352 (1984); Wold v. State, 57 Wis. 2d 344, 356-58, 204 N.W.2d 482 (1973). We recognize that there has been a "gradual merger of this court's collective thinking in respect to harmless versus prejudicial error." State v. Dyess, 124 Wis. 2d 525, 543, 370 N.W.2d 222 (1985). Regardless of whether the test is prejudicial error or harmless error, or .whether any difference between the two remains, our conclusion in this case is the same. The admission of DeLao's statements is sufficient to undermine our confidence in the outcome of her trial. See id. at 545.
The court of appeals appeared to assume that DeLao's new trial should encompass all three of the charges for which she was convicted, including the weapons possession charge, *319and we agree. Her theory of defense was that at the time police searched her home, she did not know it contained guns. She testified that on a previous occasion, when either Stalsberg or Sabala brought a gun to her house, she demanded that it be removed. The State's position was that she was lying, and her statements to Detective Prioletta served to undermine her credibility. Thus, DeLao's decision to testify coupled with her statements to Prioletta generated the evidentiary dispute central to the weapons charge, and her conviction on that charge was contaminated by the prejudicial effect of the State's discovery violation.