Opinion of the Court
COX, Judge:1. Appellant was tried by a general court-martial composed of officer members at K.I. Sawyer Air Force Base, Michigan. Contrary to his pleas, he was convicted of wrongful use of cocaine, in violation of Article 112a, Uniform Code of Military Justice, 10 USC § 912a. He was sentenced to a bad-conduct discharge, forfeiture of $250.00 pay per month for 4 months, and reduction to airman basic. The convening authority approved the sentence on July 27, 1990, and the Court of Military Review1 affirmed on September 1, 1992. See 1992 WL 225873.2
2. We granted review of the following issues as framed by appellate defense counsel:
I
WHETHER THE MILITARY JUDGE ABUSED HIS DISCRETION BY DENYING A NEW TRIAL WHEN A WITNESS CAME FORWARD AFTER FINDINGS AND ADMITTED TO SPIKING APPELLANT’S FOOD WITH COCAINE.
II
WHETHER THE MILITARY JUDGE ABUSED HIS DISCRETION BY DENYING A NEW TRIAL IN SPITE OF A POST-TRIAL OSI INVESTIGATION WHICH SIGNIFICANTLY UNDERMINED THE INTEGRITY OF THE URINALYSIS PROGRAM AT APPELLANT’S BASE AND REVEALED THAT THE SPECIMEN CUSTODIAN IN APPELLANT’S CASE ADMITTED TO USING DRUGS AND TAMPERING WITH AT LEAST ONE SPECIMEN.
III
WHETHER COUNSEL FOR APPELLANT IS ENTITLED TO HAVE ACCESS TO DOCUMENTS SEALED BY A TRIAL COURT UNDER RCM 701(g)(2), ABSENT OVERRIDING CONCERNS FOR NATIONAL SECURITY OR THE SAFETY OF AN UNIDENTIFIED INFORMANT.
3. As to the first issue, we hold that the military judge did not err by denying appellant a new trial. However, he did err when he denied appellant the opportunity to reopen his case to present newly discovered evidence to the court-martial. This holding renders Issue II moot. (As to Issue III, see n. 2, supra.)
4. Appellant was charged with using cocaine sometime between October 13 and 20, 1988. He denied using the substance and vigorously contested the urinalysis evidence presented by the Government. Nevertheless, he was found guilty. Following findings, the proceedings recessed for the evening. It was during that recess that Mr. Sean Duffy came forward and revealed new evidence in the form of an admission of personal misconduct which, if true, arguably could exculpate appellant from any criminal liability. He furnished an affidavit that was presented to the military judge in support of the motion to reopen appellant’s case.
5. According to Mr. Duffy, he attended a party on October 8, 1988, with appellant and several high school friends. The party was hosted by appellant’s parents in their New *246Jersey home. Mr. Duffy admits that, sometime during the party, he used the glass on a framed picture to line some cocaine. Appellant was under the impression that Duffy inhaled the lines of cocaine. Mr. Duffy now swears that he did not. Rather, Mr. Duffy says that, after appellant’s mother admonished him and asked him to leave, he surreptitiously “blew [the cocaine] across a plate of cookies that were sitting on the table.” When appellant returned to his base, he took some of those cookies back with him and presumably consumed some or all of the cookies in the days prior to the random urinalysis.3
6. The evening after findings, defense counsel represents that he became aware of this information for the first time. The next morning, he moved for a mistrial on the basis of newly discovered evidence. RCM 915, Manual for Courts-Martial, United States, 1984. The military judge denied this motion.4
7. Defense counsel then requested the opportunity to reopen his case to present this newly-discovered information to the members for reconsideration of the findings.
8. The military judge applied the same legal standard for deciding whether appellant would be allowed to reopen his case as hé applied to the motion for a mistrial. In both instances, he applied the same rules he would apply to a motion for a new trial. RCM 1210(f)(2). Thereafter, he denied the motion. Perhaps he was guided by our cases. See United States v. Eshalomi, 23 MJ 12, 28 (1986), where Judge Cox, concurring, stated:
If the discovery [of new evidence] occurs prior to announcement of the sentence and if the accused so moves, the military judge has the option of reopening the trial for the purpose of presenting the evidence to the court-martial. In considering the motion, I would adopt the same test that is used to determine if a new trial would be warranted by the discovery of new evidence. “[T]he newly discovered evidence, if considered by a court-martial in the light of all other pertinent evidence, would probably produce a substantially more favorable result for the accused.”
9. Defense counsel also moved that the military judge “direct a verdict” for appellant. The military judge likewise denied this motion. The basis for all of the military judge’s rulings was that the “due diligence” requirement of the newly-discovered-evidence rule, RCM 1210(f)(2), had not been met. The military judge ruled as follows:
A very crucial aspect of the rules about newly discovered evidence is whether it is such that it would not have been discovered at the time of trial through the exercise of due diligence. Based on the evidence and the defense representations before me, I find that the evidentiary matters raised to me from Mr. Duffy fall under the category of matters that would have been discovered through due diligence.
10. Thus we are faced with two important questions regarding this issue. First, did the military judge apply the correct legal standard for consideration of the various trial motions? Second, if he did use the correct standard, did he abuse his discretion in applying the facts of this case to the appropriate rule of law?
11. As to the motion for mistrial, it is clear that the military judge treated the motion as a petition for new trial based upon newly discovered evidence. RCM 1210. In a real sense, a motion for a mistrial, which occurs after findings have been announced, is *247asking the judge for a new trial, although there may be many reasons for mistrials other than newly discovered evidence. However, mistrial motions are governed by a different rule. RCM 915 provides:
The military judge may, as a matter of discretion, declare a mistrial when such action is manifestly necessary in the interest of justice because of circumstances arising during the proceedings which cast substantial doubt upon the fairness of the proceedings. A mistrial may be declared as to some or all of the charges, and as to the entire proceedings or as to only the proceedings after findings.
(Emphasis added.)
12. Thus, the standard for a mistrial requires the military judge to view the proceedings from the viewpoint of whether it is necessary to start the case (or a portion of it) over to ensure justice and fairness. The fact that new evidence has been discovered during the proceedings may be a reason for granting a mistrial, but the “newly discovered evidence rule” is not the test. As we have previously stated, “a mistrial is a drastic remedy and is reserved for only those situations where the military judge must intervene to prevent a miscarriage of justice.” United States v. Garces, 32 MJ 345, 349 (CMA 1991). Because a mistrial is such “a drastic remedy,” we have recognized that the military judge should explore other remedies, such as curative instructions or permitting a party to reopen the case. United States v. Evans, 27 MJ 34, 39 (CMA 1988), cert, denied, 488 U.S. 1011, 109 S.Ct. 797, 102 L.Ed.2d 788 (1989).
13. It is now beyond doubt in military jurisprudence that a military judge is empowered to reopen a case even after findings have been announced. United States v. Scaff, 29 MJ 60 (CMA 1989); United States v. Griffith 27 MJ 42 (CMA 1988). RCM 913(c)(5) recognizes: “A military judge may, as a matter of discretion, permit a party to reopen its case after it has rested.”
14. However, we believe the literal and strict application of the newly-discovered-evidence rule, which implements the statutory rule found in Article 73, UCMJ, 10 USC § 873, during a trial, is inappropriately severe. Indeed, in United States v. Ray, 26 MJ 468 (CMA 1988), cert, denied, 488 U.S. 1010, 109 S.Ct. 797, 102 L.Ed.2d 788 (1989), Chief Judge Sullivan stated that RCM 913(c)(5) created a “flexible standard ... which sought ... to avoid the granting of motions for [a] finding of not guilty where available evidence had not been presented by the prosecution.” 26 MJ at 470, citing Drafter’s Analysis, Manual, supra at A21-55. We also recognized: “This procedural rule implies that the moving party should proffer some reasonable excuse for its request to reopen its case.” 26 MJ at 471.
15. Let there be no doubt that a party should not be allowed to profit from his or her lack of due diligence in investigating the case or to play games with the court and “hide” evidence, awaiting the verdict before springing the evidence upon opponents. See generally 75 AmJur2d, Trial § 382 (1991). But the same policy considerations for granting new trials long after completion of a trial do not necessarily apply to motions to reopen a case before the trial is over. See Fed. R.Crim.P. 33 (7-day rule/2-year rule). If the trial is still on-going, the parties are only marginally inconvenienced; all decision makers are in place; and the interests of justice can only be served by a complete and fair hearing of all the relevant evidence then available. Compare provisions concerning jury trial with bench trial in Fed.R.Crim.P. 33.
16. Unlike most civilian and federal jury trials, a court-martial composed of members plays a dual role in the trial. The court-martial members adjudicate the issue of guilt and, upon a finding of guilty, they pass judgment upon the sentence to be imposed. RCM 924 recognizes that members, upon their own motion, may reconsider a finding of guilty at any time before the announcement of sentence. In other words, the court-martial process is designed to be fair and, at the same time, to give finality to the case. Allowing an accused to reopen his or her case, even after findings, upon a proper showing that new and relevant evidence has been *248discovered which, if true, may well vindicate him, is not alien to the ideals of the court-martial system. Even the prosecutor has the duty to reveal newly discovered evidence, notwithstanding the fact that the case has been completed and deliberations have commenced. United States v. Eshalomi, supra, ¶ 8.
17. We decline the opportunity, however, to fashion a particular rule to guide military judges in exercising discretion on whether to permit a party to reopen his or her case. Suffice it to say, normal rules of relevance, cumulativeness, adequacy of substitutes in the record, completeness of the record, the interests of justice, the elimination of post-trial attacks on the verdict, as well as mitigation of ineffective-assistance-of-counsel claims are all considerations. But the primary consideration should be whether discovery of the new evidence is bona fide and whether the new evidence, if true, casts substantial doubt upon the accuracy of the proceedings; that is, a rule which is not only fair to the defendant, but fair to the prosecution as well.
18. The question then remaining in this case is whether the military judge abused his discretion by denying appellant the right to reopen his case to present the new evidence. One test for abuse of discretion is whether the military judge’s rulings “materially prejudice] the substantial rights of the accused.” Art. 59(a), UCMJ, 10 USC § 859(a). We conclude in this case that they did.
19. First, notwithstanding the military judge’s ruling that the witness could have been discovered had appellant used due diligence, arguably quite the opposite was the case.5 Defense counsel did not lack due diligence for his failure to interview attendees at the party. An expert consultant opined that, based upon the test results of appellant’s urine sample, any ingestion of cocaine had occurred after the date of the party. Accordingly, the focus of the defense did not turn to what may have happened at the party until they learned that appellant ate some of the contaminated cookies at a later time, within the window suggested by the expert. In this regard, we note that the Court of Military Review was wrong in its first opinion when it said, “[G]laringly absent is any offer of proof, affidavit, or other assertion that the appellant ever consumed any of the allegedly adulterated cookies.” 1992 unpub. op. at 4 n. 2. Trial defense counsel’s brief in support of the motion for a new trial proffers that the cookies “were consumed by both appellant and his co-workers during October 1988.” (Attachment 1 to Appellate Exhibit LXXXVIII at 5).
20. Furthermore, Mr. Duffy purportedly did not come forward and admit his involvement until after he was advised of appellant’s conviction. There was nothing to discover until Mr. Duffy presented himself and his evidence. In this circumstance we will not hold appellant responsible for the delay.6
21. Second, the court-martial was still assembled when the motion was made. It should have been evident to the military judge from the tenor of the questions by the court members to appellant on the witness stand that the members were acutely interested in whether appellant could have innocently ingested the unlawful substance. It is not at all clear that the testimony of Mr. Duffy would not have given the members cause for reasonable doubt as to appellant’s guilt. We have stated:
Suffice it to say, ... [the new information] give[s] us pause as to the completeness of the factfinding process. Obviously, [the *249new information] ha[s] not been tested in the crucible of trial, and we can intimate no judgment whatever as to the ultimate conclusions of veracity or weight a factfinder might attach to them. Nevertheless, whether we ascribe [the new information’s] absence from the process to the fog of command influence, the inability of counsel to ascertain the facts, misguided friends, pusillanimous witnesses, outright peijury, or just plain bad luck, this trial has to go back to square one. On this record, despite the best of intentions and efforts of the military judge, we cannot conclude, in a due process sense, that appellant has yet enjoyed a full and complete trial. Far too much of the information that needed to be evaluated by a factfinder, in order to assess appellant’s culpability, was not. We conclude that the military judge abused his discretion in concluding that the evidence probably would not produce a substantially more favorable result for appellant. ROM 1210(f)(2)(C); Art. 73, UCMJ, 10 USC § 873.
United States v. Singleton, 41 MJ 200, 206-07 (CMA 1994).
The decision of the United States Air Force Court of Military Review on further review is reversed. The findings and sentence are set aside. The record of trial is returned to the Judge Advocate General of the Air Force. A rehearing may be ordered.
Chief Judge SULLIVAN and Judges GIERKE and WISS concur.. See 41 MJ 213, 229 n. * (1994).
. After this case was earlier set for oral argument, this Court vacated the hearing notice, set aside the decision of the Court of Military Review, and remanded the record to the Court of Military Review for reconsideration in light of our opinion in United States v. Branoff, 38 MJ 98 (CMA 1993). See 39 MJ 334 (CMA 1993). These matters fall within the ambit of the third granted issue. The Court of Military Review reconsidered its earlier decision and, in a subsequent opinion, once again affirmed the approved findings and sentence. 1994 WL 259480. Our hold*246ing makes it unnecessary to decide Issue III at this time.
. On October 18, 1988, appellant was informed that he would have to submit a urine sample on October 20, 1988. There is no question that appellant complied with his instructions, and there is no contest as to the conclusion that the sample tested positive.
. Defense counsel also renewed his motion after trial by requesting a post-trial session under Article 39(a), Uniform Code of Military Justice, 10 USC § 839(a), to consider evidence on the issue. The military judge denied that motion by ratifying his earlier decisions on the matter. Unquestionably, the judge could have entertained this matter in a proceeding under United States v. DuBay, 17 USCMA 147, 37 CMR411 (1967), and if the information was raised for the first time there, then he could have applied, as he did, RCM 1210, Manual for Courts-Martial, United States, 1984, standards for resolution. Arguably, as indicated, what appellant really sought to do later was to reopen his case.
. We are not saying that a military judge may never refuse to reopen a case because of a lack of due diligence. However, our case law suggests that RCM 913(c)(5) is most often used by the Government to fix a gap in the proof of a case, gaps which may well have been the result of a lack of "due diligence.” See United States v. Ray, 26 MJ 468, 470 (CMA 1988), cert, denied, 488 U.S. 1010, 109 S.Ct. 797, 102 L.Ed.2d 788 (1989).
. In point of fact, a ruling of "lack of due diligence” invoked against the conduct of a defense counsel raises the awesome specter of "ineffective-assistance-of-counsel” claims. See United States v. Scott, 24 MJ 186 (CMA 1987) (counsel’s failure to promptly investigate and prepare accused’s sole defense of alibi was ineffective assistance of counsel).