Opinion
This appeal presents the question whether a probation department has a duty to preserve and disclose a urine sample when that *218 sample is used as the basis for revocation of probation, We hold that the department, having requested a revocation hearing based on the test results of a urine sample, has a duty to preserve and disclose the sample even in the absence of a request therefor.
On July 1, 1977, defendant Frank Moore was charged by information with five counts of selling controlled substances in violation of Health and Safety Code section 11379, subdivision (a). In an information filed December 7, 1977, defendant was alleged to have unlawfully possessed phencyclidine (PCP), in violation of Health and Safety Code section 11377, subdivision (a).
Defendant pled guilty to violation of Health and Safety Code section 11377, subdivision (a) and was granted probation for 3 years on certain conditions, including that he spend the first 150 days in county jail. Defendant also pled guilty to count I of the information alleging violation of Health and Safety Code section 11379, subdivision (a); probation was granted and the sentence was ordered to run concurrently with that imposed in the other case.
In 1979, after a urine sample tested positive for PCP, an evidentiary hearing was held. Defendant was found to be in violation of probation. He was sentenced to a three-year suspended sentence, the probationary period was extended two years, and defendant was ordered to submit to regular narcotic testing.
On January 13, 1981, following several tests showing the presence of PCP in defendant’s urine, the violation was held in abeyance and defendant was admonished that any more “dirty tests” would result in imposition of a state prison sentence.
On January 20, 1981, at the direction and in the presence of his probation officer, defendant supplied a urine sample which was sent to the Los Angeles County laboratory for analysis. Three tests were performed, all indicating the presence of PCP. When the results of the chemical analysis were received by the probation department, defendant’s probation officer requested a hearing date for revocation of probation.
On April 2, 1981, defendant denied violating the terms of probation, his motion to substitute counsel was granted, and the matter was continued until May 4, 1981. On that date the People moved for a continuance, and defendant’s new counsel requested inspection of the urine sample. By the time of defendant’s request, however, the urine sample had been discarded.
*219 At the hearing on probation revocation, the chief toxicologist of the Los Angeles County Laboratory testified that the probation department and the laboratory had an agreement that positive samples were to be retained by the laboratory for three months unless the probation department requested retention of particular samples for a longer period. The toxicologist also testified that defendant’s urine sample taken on January 20, 1981, had tested positive for PCP. He further testified that if the sample were available at the time of the hearing, a test for PCP would reconfirm the earlier results. However, he also testified that the usefulness of retests of the sample would depend upon “who does the work. There’s a lot of incompetence in this work.”
Defendant’s probation officer testified that he requested a hearing on revocation of probation upon reviewing the results of the test performed on defendant’s urine sample of January 20, 1981. The probation officer also stated that he did not request that the sample be retained by the laboratory.
At the conclusion of the hearing, defense counsel argued in essence that the failure of the prosecution to preserve the urine sample denied the defendant the opportunity to independently examine the sample, and therefore deprived defendant of a fair revocation hearing. The trial court found the procedures for retention of positive samples to be reasonable, and further found defendant to be in violation of the terms and conditions of probation.
The rule we set forth in this case is not new; it merely follows from application of previously established principles regarding the duty of the government to preserve and disclose evidence material to the issue of the guilt or innocence of the defendant. That duty was enunciated in
People
v.
Hitch
(1974)
In Hitch the defendant was arrested for driving a motor vehicle while under the influence of intoxicating liquor. The defendant submitted to a breathalyzer test by breathing into a machine that trapped his breath in a glass ampoule. The presence of alcohol could be detected by comparing the sample ampoule to a reference ampoule. The officer tested defendant’s breath and concluded that alcohol was present. The officer then poured the contents of the test ampoule into a bottle and discarded the ampoule itself. The bottle was delivered to a county laboratory, which eventually disposed of its contents.
Defendant moved to suppress the results of the breathalyzer test, claiming that destruction of the test ampoule and its contents deprived him of due process of law. This court held that an investigative agency has a duty to preserve and disclose evidence material to the guilt or innocence of the
*220
accused
(People
v.
Hitch, supra,
Hitch
relied on the reasoning of
United States
v.
Bryant
(D.C.Cir. 1971)
Other federal courts have suggested that the government’s failure to preserve discoverable evidence amounts to a denial of due process: “Loss or destruction of relevant evidence by the government not only raises general questions of the fundamental fairness of a criminal trial, but may also deny a defendant the right to compulsory process.”
(Government of Virgin Islands
v.
Testamark
(3d Cir. 1978)
That the government has an obligation to preserve and disclose material evidence is thus clear. The question becomes whether the urine sample in this case constituted such material evidence.
When the evidence is no longer in existence, the burden of establishing that the evidence is material is met when the defendant shows that there is “a reasonable possibility that the evidence, if preserved, would have constituted favorable evidence on the issue of guilt or innocence.
(People
v.
Hitch, supra,
For purposes of materiality, the evidence in this case is also similar to a semen sample obtained from the vagina of a rape victim, which has been found to be necessarily material evidence requiring preservation.
(People
v.
Nation, supra,
Because the evidence in question is no longer available, it is impossible for this or any court to determine whether in fact the urine sample would have been favorable evidence to the defendant. However, it is the government’s loss of evidence that requires speculative inquiry as to its materiality. Of course, when the evidence is available but has been suppressed by the prosecution, the court is in a better position to determine whether the suppressed evidence is substantially material. This court specifically distinguished such situations in
Hitch.
Referring to
Brady
v.
Maryland
(1963)
In this case, the loss of the evidence necessarily means that the defendant will be unable to make a showing of materiality beyond claiming that he did not ingest PCP. This the defendant did by denying in open court that he violated probation.
Our attention has been drawn to
People
v.
Chambers
(1980)
Even assuming the validity of the Chambers rule, the situation in this case is quite different. Here, the lost evidence constitutes the only evidence of a violation of probation. Thus, the mere denial of violation of probation implies denial of use of PCP, and therefore suffices as a showing that the lost evidence would have been material. Thus, we reject the suggestion that defendant’s failure to testify at the probation revocation hearing rendered the lost evidence immaterial.
Having concluded that the lost urine sample constituted material evidence that might have been helpful to the defense, we must decide what, if any, sanctions are appropriate for the government’s failure to preserve and disclose the urine sample. The dispute on this issue involves the relevant standard with which the prosecution must comply, and whether the procedure in this case meets that standard. As we shall see, however, the standard is clear, and the prosecution has failed to meet it in this case.
The sanctions to be imposed in any case depend upon the particular circumstances attendant to the loss or destruction of the material evidence.
(People
v.
Hitch, supra,
*223
The People contend that the prosecution need only employ reasonable methods to preserve evidence, citing
People
v.
Nation, supra,
There is language in
People
v.
Nation, supra,
The procedure used in this case fails to meet the required standard. The county preserved positive samples for 90 days, or longer if a request was made for a particular sample. However, there was no showing that such requests were regularly made when revocation hearings were scheduled. Thus, the government has failed to show that it has reasonably attempted to preserve samples until the hearings for which they have been taken. Without a showing that requests to retain samples are routinely made and honored, the preservation of a particular sample depends upon the fortuitous circumstance whether the hearing has been held within 90 days. Such a system fails to be a reasonable measure designed to ensure the preservation of material evidence, because it fails to employ rigorous and systematic procedures designed to preserve material evidence for the hearing in which its results are introduced.
We therefore hold that the urine sample in this case was material evidence giving rise to a duty to preserve and disclose the sample. The government has failed to show that rigorous and systematic procedures were taken to preserve the sample. Therefore, evidence regarding results of tests of the *224 urine sample must be excluded. Because results of the test constitute the only evidence regarding defendant’s violation of probation, the judgment revoking defendant’s probation is reversed.
Bird, C. J., Mosk, J., Kaus, J., Reynoso, J., and Grodin, J., concurred.
Richardson, J., concurred in the judgment.
