The respondent district court issued a contempt citation against the petitioner, Frederick Miller, when he refused to answer questions relating to murder charges against the defendant, Lawrence Aoki. We issued a rule to show cause, and now discharge the rule in part and make the rule absolute in part.
I.
In February 1986, the defendant, Lawrence Aoki, was charged in the Denver District Court with two counts of murder in the first degree, section 18-3-102, 8B C.R.S. (1986), and two counts of mandatory sentence for a violent crime, section 16-11-309, 8B C.R.S. (1986). The charges arose out of the defendant’s commission of two homicides on February 6, 1986, while he was allegedly suffering from a cocaine-induced mental disorder. The Colorado State Public Defender’s Office was appointed to represent Aoki.
After the defendant was arrested, the Public Defender’s office retained Dr. Frederick Miller, a psychiatrist, to perform a mental status evaluation of Aoki. The primary purposes of the examination and consultation were to determine the feasibility of a mental status defense and to advise defense counsel on trial tactics and strategy. Dr. Miller met with Aoki and advised him that his evaluation was protected by the attorney-client privilege, section 13-90-107(l)(b), 6 C.R.S. (1986 Supp.), and that any statements made during the evaluation would remain confidential until Aoki waived the privilege. After the evaluation, Dr. Miller reported his impressions and advice to defense counsel. Dr. Miller did not prepare a written report.
Aoki entered a plea of not guilty by reason of insanity, section 16-8-103, 8A C.R.S. (1986). While preparing for trial, the prosecution determined through an examination of jail records that Dr. Miller visited Aoki. Predicting that he would be a witness, the prosecution moved to endorse Dr. Miller as a witness at Aoki’s upcoming sanity trial. On September 11, 1986, the district court permitted the endorsement *836over the objection of defense counsel. Defense counsel thereafter filed a “Petition for Relief Pursuant to [C.A.R.] 21,” and sought an order prohibiting endorsement of Dr. Miller as a prosecution witness. We denied the petition.
On September 15, 1986, trial began on the issue of Aoki’s sanity at the time of the commission of the offense. The district court denied Dr. Miller’s motion to quash the prosecution subpoena, and Dr. Miller sought relief in this court pursuant to C.A.R. 21. We issued a rule to show cause, but ultimately discharged the rule pursuant to a motion filed by the prosecution. In the motion, the prosecution advised this court that Aoki’s sanity trial had proceeded to a verdict without the testimony of Dr. Miller, and that the jury found the defendant sane. The prosecution therefore claimed that the “issue as to quashal [sic] of subpoenas [was] moot as there [was] no longer a case or controversy.”
After we discharged the rule to show cause, the defendant entered a plea of not guilty by reason of impaired mental condition, section 16-8-103.5, 8A C.R.S. (1986). The prosecution again subpoenaed Dr. Miller to testify at a pretrial hearing on a motion to suppress and at the guilt phase of Aoki’s trial. The purpose of the prosecution’s intended examination was to establish the defendant’s culpable mental state at the time of the commission of the crimes, and the voluntariness of incriminating statements made by the defendant after his arrest. Dr. Miller again moved to quash the subpoena, and the motion was denied by the trial court. Dr. Miller petitioned this court for an order requiring the district court to quash the subpoena. We denied the petition on January 15, 1987.
On February 9, 1987, a hearing was held on Dr. Miller’s refusal to testify. The prosecution called Dr. Miller as a witness, and, in response to the prosecution’s inquiry as to what Aoki told him regarding “the events of February 6, 1986, particularly as to [Aoki’s] mental condition at that time,” Dr. Miller declined “to answer any further questions about [his] examination of Mr. Aoki....” The district court entered an order of contempt against Dr. Miller, and imposed a fine of $100 per day until he agreed to testify. The district court later stayed execution of the fine pending resolution of this original proceeding.
Dr. Miller now petitions this court for an order under C.A.R. 21 compelling the district court to quash the subpoena of Dr. Miller and to vacate the contempt citation. We conclude that Dr. Miller could not be compelled at the February 9, 1987 hearing to disclose confidential statements made to him by the defendant, but hold that Dr. Miller’s petition for an order requiring the court to quash the subpoena is premature.
II.
We have never considered whether, absent a waiver, a defendant’s disclosures to a defense-retained psychiatrist are protected by the attorney-client privilege. However, a majority of the courts that have addressed the question have held that such communications are protected from disclosure either under the attorney-client privilege or the sixth amendment to the United States Constitution. See, e.g., United States v. Alvarez, 519 F.2d 1036 (3d Cir. 1975); United States ex rel. Edney v. Smith, 425 F.Supp. 1038 (E.D.N.Y.1976); Houston v. State, 602 P.2d 784 (Alaska 1979); People v. Lines, 13 Cal.3d 500, 119 Cal.Rptr. 225, 531 P.2d 793 (1975) 1; State v. Toste, 178 Conn. 626, 424 A.2d 293 (1979); State v. Pratt, 284 Md. 516, 398 A.2d 421 (1979); People v. Hilliker, 29 Mich.App. 543, 185 N.W.2d 831 (1971); *837State v. Kociolek, 23 N.J. 400, 120 A.2d 417 (1957); Ballew v. State, 640 S.W.2d 237 (Tex.Crim.App.1980). But see, e.g., Noggle v. Marshall, 706 F.2d 1408 (6th Cir.1983), cert. denied, 465 U.S. 1010, 104 S.Ct. 530, 78 L.Ed.2d 712 (1983).
Colorado’s privilege statute, section 13-90-107(l)(b), 6 C.R.S. (1986 Supp.), provides:
An attorney shall not be examined without the consent of his client as to any communication made by the client to him or'his advice given thereon in the course of professional employment; nor shall an attorney’s secretary, paralegal, legal assistant, stenographer, or clerk be examined without the consent of his employer concerning any fact, the knowledge of which he has acquired in such capacity.
The attorney-client privilege extends to confidential communications by or to the client in the course of gaining counsel, advice, or direction with respect to the client’s rights or obligations.2 Losavio v. District Court, 188 Colo. 127, 133, 533 P.2d 32, 35 (1975); Denver Tramway Co. v. Owens, 20 Colo. 107, 128, 36 P. 848, 855 (1894). Although section 13-90-107(l)(b) does not by its terms protect disclosures to a defense-retained psychiatrist, we have held that the privilege may be applied to communications between the client and agents of his attorney.3 See Bellman v. District Court, 187 Colo. 350, 531 P.2d 632 (1975) (statements made to an insurance investigator are privileged); A. v. District Court, 191 Colo. 10, 21, 550 P.2d 315, 324 (1976) (in order to come within the protection of the attorney-client privilege, there *838must be a communication between the client and his attorney or the attorney’s agent), cert. denied, 429 U.S. 1040, 97 S.Ct. 737, 50 L.Ed.2d 751 (1977). See also Kay Laboratories, Inc. v. District Court, 653 P.2d 721, 723 (Colo.1982). The agency rule recognizes that the complexities of practice prevent attorneys from effectively handling clients’ affairs without the help of others. The assistance of these agents “being indispensable to [the attorney’s] work ..., the privilege must include all persons who act as the attorney’s agents.” 8 J. Wigmore, Wigmore on Evidence § 2301, at 583 (1961). See also 2 J. Weinstein & M. Berger, Weinstein’s Evidence If 503(a)(3)[01], at 503-27 to -28 (1986); United States v. Kovel, 296 F.2d 918 (2d Cir.1961); People v. Lines, 13 Cal.3d 500, 119 Cal.Rptr. 225, 531 P.2d 793 (1975); City of San Francisco v. Superior Court, 37 Cal.2d 227, 231 P.2d 26 (1951); People v. Ryan, 30 Ill.2d 456, 197 N.E.2d 15 (1964); Asbury v. Beerbower, 589 S.W.2d 216 (Ky. 1979). It is now settled that a psychiatrist retained by defense counsel to assist in the preparation of the defense is an agent of defense counsel for purposes of the attorney-client privilege. See, e.g., People v. Lines, 13 Cal.3d 500, 119 Cal.Rptr. 225, 531 P.2d 793 (1975); State v. Pratt, 284 Md. 516, 398 A.2d 421 (1979); Ballew v. State, 640 S.W.2d 237 (Tex.Cr.App.1982). See also Criminal Justice Mental Health Standards § 7-3.3(b), commentary at 7-85 (1984).
In this case, the trial court found that Dr. Miller was hired by defense counsel to examine the defendant and to assist counsel in entering a plea and preparing for trial. Because Dr. Miller is an agent of defense counsel who was retained for the purposes of providing a psychiatric evaluation of the defendant’s condition, the defendant’s confidential communications to him were privileged under section 13-90-107(l)(b). Absent a waiver, Dr. Miller could not be held in contempt at the February 9,1987 hearing for his refusal to reveal the content of those communications. Thrap v. People, 192 Colo. 341, 345, 558 P.2d 576, 578 (1977).
The prosecution claims that the defendant impliedly waived the attorney-client privilege by placing his mental condition in issue. We disagree, as have the majority of courts that have considered the question. See, e.g., United States v. Alvarez, 519 F.2d 1036 (3d Cir.1975); Houston v. State, 602 P.2d 784 (Alaska 1979); People v. Lines, 13 Cal.3d 500, 119 Cal.Rptr. 225, 531 P.2d 793 (1975); State v. Pratt, 284 Md. 516, 398 A.2d 421 (1979); State v. Kociolek, 23 N.J. 400, 129 A.2d 417 (1957). But see People v. Edney, 39 N.Y.2d 620, 385 N.Y.S.2d 23, 350 N.E.2d 400 (1975).4
A waiver of the attorney-client privilege may be express or implied, and the burden of establishing a waiver is on the party seeking to overcome the privilege. Clark v. District Court, 668 P.2d 3, 8 (Colo.1983). An implied waiver must be supported by evidence showing that the privilege holder, by words or conduct, has impliedly forsaken his claim of confidentiality with respect to the communication in question. Id.
In this case, the defendant’s assertion of a mental status defense alone does not fairly indicate an implied waiver of the privilege. “Only a foolhardy lawyer would determine tactical and evidentiary strategy in a case with psychiatric issues without the guidance and interpretation of psychiatrists and others' skilled in the field.” United States ex rel. Edney v. Smith, 425 F.Supp. 1038, 1047 (E.D.N.Y.1976), aff'd, 556 F.2d 556 (2d Cir.), cert. denied, 431 U.S. 958, 97 S.Ct. 2683, 53 L.Ed.2d 276 (1977). Defense counsel should not run the risk that a psychiatrist who is consulted to prepare for trial may be forced to become an involuntary prosecution witness. A psychiatrist cannot form an opinion without inquiring about the defendant’s mental condition and the facts surrounding the alleged crime. The defendant has a right to *839require the prosecution to investigate its own case, see United States v. Wright, 489 F.2d 1181, 1185 (D.C.Cir.1973); State v. Pratt, 284 Md. 516, 524, 398 A.2d 421, 426 (1979), and legitimately may expect that disclosures made to the psychiatrist will not be used as evidence for the prosecution. United States v. Alvarez, 519 F.2d 1036, 1047 (3d Cir.1975).
If, as the prosecution urges, the defendant’s claim of impaired mental condition creates a waiver of his right to assert the attorney-client privilege as to disclosures made to a defense-retained psychiatrist, defense counsel’s ability to prepare a mental status defense would be materially curtailed. The utility and efficacy of psychiatric examination is dependent in great part upon the defendant’s ability to communicate freely and confidentially with his examining doctor, and the rule proposed by the prosecution would chill the defendant’s dialogue with a psychiatrist retained by defense counsel to assist in the defense. Psychiatric consultation is, in many cases, one of the “raw materials integral to the building of an effective defense,” Ake v. Oklahoma, 470 U.S. 68, 77, 105 S.Ct. 1087, 1094, 84 L.Ed.2d 53 (1985), and psychiatry has come to play a “pivotal role” in criminal proceedings where the defendant’s mental condition is in issue. Id. at 79, 105 S.Ct. at 1095. As the Court in Ake stated:
[W]hen the State has made the defendant’s mental condition relevant to his criminal culpability and to the punishment he might suffer, the assistance of a psychiatrist may well be crucial to the defendant’s ability to marshal his defense. In this role, psychiatrists gather facts, both through professional examination, interviews, and elsewhere that they will share with the judge or jury; they analyze the information gathered and from it draw plausible conclusions about the defendant’s mental condition, and about the effects of any disorder on behavior; and they offer opinions about how the defendant’s mental condition might have affected his behavior at the time in question.
Id. at 80, 105 S.Ct. at 1095 (emphasis added).
A waiver based solely on the defendant’s assertion of a mental status defense seriously compromises the attorney’s consultation with a psychiatrist retained to assist in the defense, and frustrates the policy underlying the attorney-client privilege to insure “candid and open discussion by the client to the attorney without fear of disclosure.” Losavio v. District Court, 188 Colo. 127, 132, 533 P.2d 32, 34 (1975). The prosecution’s examination of Dr. Miller was conducted in a vacuum, and there is nothing at the February 9, 1987 hearing, other than the defendant’s claim of impaired mental condition, upon which to base a waiver. Dr. Miller was not questioned in the context of an adversarial proceeding, but rather at a pretrial hearing that was designed to provide a basis for presenting the issue to this court in an original proceeding. Based on the limited record before us, the defendant did not by words or conduct forsake his claim of confidentiality and impliedly waive the privilege.5 The *840district court’s contempt order was in error, and the court is hereby ordered to vacate the finding of contempt.6
III.
Although Dr. Miller could not be compelled at the February 9, 1987 hearing to disclose privileged information, we cannot rule on the record before us that the subpoena must be quashed. A party seeking to invoke the original jurisdiction of this court must establish circumstances justifying the exercise of this court’s power under C.A.R. 21. Groendyke Transportation, Inc. v. District Court, 140 Colo. 190, 194, 343 P.2d 535, 537 (1959). The burden is on the petitioner to establish clearly that the respondent court is proceeding without or in excess of its jurisdiction, or that the court has abused its discretion. Brewer v. District Court, 655 P.2d 819, 820 (Colo.1982).
The record in the district court is not sufficient for us to determine whether the subpoena to Dr. Miller was proper. Dr. Miller alleges that the prosecution’s subpoena violates the defendant’s attorney-client privilege, and impinges upon the defendant’s privilege against self-incrimination under the fifth amendment to the United States Constitution, his rights to effective assistance of counsel under the sixth amendment to the United States Constitution, and to due process under the state and federal constitutions. However, without a well-defined record detailing the posture, content, and purpose of the examination of Dr. Miller, and other matters relevant to the defendant’s assertion of the attorney-client privilege and his constitutional privileges and rights, a decision of this court would be premature. After the defendant has presented his defense of impaired mental condition, if the prosecution wishes to call Dr. Miller as a rebuttal witness and the defendant objects to the questions posed to Dr. Miller, the court should consider the defendant’s assertion of the attorney-client privilege and his constitutional privileges and rights, including the question of whether the defendant has waived the privilege or his constitutional rights. See, e.g., Houston v. State, 602 P.2d 784 (Alaska 1979) (although statements made by the defendant during a pretrial psychiatric examination are privileged, the privilege was waived where another defense witness relied on the former’s report and the psychiatrist was called as a rebuttal witness); State v. Tensley, 249 N.W.2d 659 (Iowa 1977) (results of an examination of the defendant by a defense-retained psychiatrist are not privi*841leged; the content of the psychiatric examination, if privileged, was waived when the psychiatrist testified); State v. Mingo, 11 N.J. 576, 392 A.2d 590 (1978) (defendant’s right to effective assistance of counsel is subverted if an expert’s report obtained for defense purposes is used by the prosecution at trial, unless the defendant signifies an intention to use expert testimony at trial); 2 J. Weinstein & M. Berger, Weinstein’s Evidence 11503(a)(3)[01], at 503-27 to -28 (1986) (a client’s disclosures to a non-testifying, defense-retained expert are privileged; observations, conclusions, and information derived from sources other than the client’s communications are not privileged).
Accordingly, the rule is made absolute as to the trial court’s order of contempt, and is discharged as to the propriety of the subpoena of Dr. Miller.
ROVIRA, J., concurs in the result only.. The concurrence asserts that People v. Lines, 13 Cal.3d 500, 119 Cal.Rptr. 225, 531 P.2d 793 (1975), is inapposite because it is based on statutory authority different than Colorado’s privilege statute. See concurrence at 842, infra. Quite to the contrary, the California Supreme Court’s decision in Lines was based on the court’s earlier decision in City of San Francisco v. Superior Court, 37 Cal.2d 227, 231 P.2d 26 (1951), which held, based upon a privilege statute identical in every material respect to Colorado’s statute, that a client may submit to an examination of a defense-retained physician without fear that the latter will be compelled to reveal information disclosed to the physician. See People v. Lines, 13 Cal.3d at 510, 119 Cal. Rptr. at 23-32, 531 P.2d at 799-800. Lines is not inapposite.
. Contrary to the concurrence’s suggestion (pg. 842, infra ), the privilege statute, section 13-90-107(l)(b), 6 C.R.S. (1986 Supp.), is a codification of the common law attorney-client privilege. See People v. Swearingen, 649 P.2d 1102, 1104 (Colo.1982).
. Because the attorney-client privilege prevents an attorneys "secretary, paralegal, legal assistant, stenographer, or clerk" from being examined concerning "any fact, the knowledge of which he has acquired in such capacity,” the concurrence apparently contends that communications to agents of defense counsel are not privileged unless the agent is "similar” to an attorney's secretary, paralegal, legal assistant, stenographer, or clerk. A similar argument was advanced by Chief Justice Pringle in his dissent to Bellman v. District Court, 187 Colo. 350, 531 P.2d 632 (1975), and did not prevail. We reject it in this case as well.
The purpose of extending the privilege to certain members of an attorney’s staff is to prevent an adverse party from examining third persons who typically might overhear or gain knowledge of a client's communications to an attorney. City of San Francisco v. Superior Court, 37 Cal.2d 227, 231 P.2d 26 (1951). The purpose is not, as the concurrence suggests, to describe the sum total of agents to whom the privilege applies. The distinction was ably described by Justice Traynor in City of San Francisco v. Superior Court:
The statute specifically extends the client’s privilege to preclude examination of the attorneys secretary, stenographer, or clerk regarding information of communications between attorney and client acquired in such capacities, to rule out the possibility of their coming within the general rule that the privilege does not preclude the examination of a third person who overhears or otherwise has knowledge of communications between a client and his attorney. It does not follow, however, that intermediate agents of communication between attorney and client fall within that general rule. Had [the client] himself described his condition to his attorneys there could be no doubt that the communication would be privileged and that neither the attorney nor [the client] could be compelled to reveal it, even though a client is not listed in section 1881(2) among those who cannot be examined. It is no less the client’s communication to the attorney when it is given by the client to an agent for transmission to the attorney, and it is immaterial whether the agent is the agent of the attorney, the client, or both. The client's freedom of communication requires a liberty of employing other means than his own personal action. The privilege of confidence would be a vain one unless its exercise could be thus delegated. A communication, then, by any form of agency employed or set in motion by the client is within the privilege.
[[Image here]]
Thus, when communication by a client to his attorney regarding his physical or mental condition requires the assistance of a physician to interpret the client’s condition to the attorney, the client may submit to an examination by the physician without fear that the latter will be compelled to reveal the information.
37 Cal.2d at 236-37, 231 P.2d at 30-31 (emphasis in original and citations omitted). The concurrence’s restricted view of the agency doctrine is both out of step with the longstanding prevailing view, see text at pg. 838, and represents a serious impediment to a client’s candid communications with anyone other than the attorney or certain members of his staff.
. People v. Edney, 39 N.Y.2d 620, 385 N.Y.S.2d 23, 350 N.E.2d 400 (1975), upon which the concurrence relies, represents the clear minority view and has been sharply criticized by the American Bar Association as "confused" and "unpersuasive." See Criminal Justice Mental Health Standards § 7-3.3, commentary at 7-85, 7-86 n. 20 (1986).
. Our opinion is consistent with the Criminal Justice Mental Health Standards § 7-3.3 (1984), promulgated by the American Bar Association. Standard 7-3.3(b) provides:
(b) Uses of disclosures. Whenever a mental health or mental retardation professional conducts an evaluation of defendant’s mental condition upon the request or motion of the defense, all disclosures made by defendant or the attorney during the course of the evaluation are protected by the attorney-client privilege. As to that evaluation only, the privilege is waived to the extent that discovery is permitted by standard 7-3.8(b), if:
(i) defendant gives notice pursuant to standard 7-6.3 of an intention:
(A) to raise an issue concerning defendant’s mental condition at the time of the alleged crime, and
(B) to introduce the testimony of the mental health or mental retardation professional who conducted the evaluation to support the defense claim on this issue; or,
(ii) defendant calls another mental health or mental retardation professional as an expert witness concerning defendant’s mental condition at the time of the alleged crime, and the prosecution establishes, to the court’s satisfaction, that in bad faith the defendant secured evaluations by all available qualified mental health or mental retardation professionals in the area thereby depriving the pros*840ecution of the opportunity to obtain an adequate evaluation.
This standard does not preclude a mental health or mental retardation professional from disclosing the fact that the professional evaluated a named person upon defense request.
The commentary to standard 7-3.3(b) articulates several policy reasons justifying confidentiality:
1. Waiver of confidentiality would have a "chilling effect” upon a client's willingness to confide in counsel or defense consultants.
2. Inherent prejudice results if the trier of fact learns that a mental health or mental retardation professional originally was employed by the defense.
3. If waiver is recognized the defense in essence would assist the prosecution in discharging its burden of proof.
4. The defendant would be inhibited from consulting mental health or mental retardation professionals with conflicting views for fear of generating prosecution witnesses.
5. The defense would be inhibited from consulting any mental health or mental retardation professionals even though consultation might be crucial to the case.
Id., commentary at 7-86.
.The district court’s entry of an order of contempt is invalid for other reasons. First, the prosecution had no right to examine a defense-retained expert prior to trial in a hearing contrived to present a question to this court in an original proceeding, and to obtain discovery of confidential communications between the defendant and the psychiatrist. See Crim.P. 15 and 16(11). Second, the record discloses that the court, prior to finding Dr. Miller in contempt, did not order him to respond to the prosecution’s examination. Absent evidence showing that the contemnor willfully disobeyed a specific and definite order of the court, contempt is not established. People v. Lockhart, 699 P.2d 1332 (Colo.1985); United States v. Rylander, 714 F.2d 996 (9th Cir.1983), cert. denied, 467 U.S. 1209, 104 S.Ct. 2398, 81 L.Ed.2d 355 (1984); United States v. Powers, 629 F.2d 619 (9th Cir.1980).