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Ninth Circuit: Refusal to Allow Cross-Examination of Lab Technician Violates Due Process

The U.S. Court of Appeals for the Ninth Circuit held it was a violation of due process for a district court to deny a criminal defendant the right to cross-examine a lab technician who tested a urine sample that showed positive for illegal drugs, when the sample was clearly adulterated by someone other than the defendant.

In 1998, Janice L. Perez pleaded guilty to bank robbery. She was sentenced to 77 months imprisonment to be followed by three years of supervised release. Perez started her supervised release term on March 8, 2007. On March 21, the day after she passed a urine test at the probation office, Perez reported to Freedom Recovery Services (FRS), an outside contractor used by probation officials to monitor persons on supervised release.

Perez voluntarily submitted to a urine test at FRS. She was under direct visual supervision by FRS personnel when the sample was taken and had no opportunity to adulterate or dilute the sample. According to the test results, Perez’s urine tested positive for cocaine. A second urine sample was not taken.

Perez’s urine was sent to Scientific Testing Laboratories, Inc. (STLI), the designated testing laboratory for U.S. Probation and Pretrial Services. The STLI report also showed that Perez’s urine tested positive for cocaine. However, the report indicated that the sample had been adulterated and contained abnormally low readings for creatine and the urine’s specific gravity.

Following a hearing, the district court revoked Perez’s supervised release. The court credited an assumption by Perez’s probation officer that Perez had adulterated the urine sample, notwithstanding testimony from FRS officials that Perez did not dilute or alter the sample. Further, the court disregarded testimony from FRS staff that several of its drug tests had previously been shown to be unreliable. Finally, the court rejected Perez’s request to cross-examine the STLI technician who had tested her urine. Perez appealed.

A term of supervised release may only be revoked based on credible evidence. In this case, the Ninth Circuit found the results from Perez’s urine test to be “ineluctably unreliable.” The cocaine found in the urine sample could have come from “Perez’ urine, an added substance, or another liquid.” Under such circumstances, it was a violation of Perez’s due process rights to deny her the opportunity to cross-examine the lab technician. Absent cross examination, the appellate court held, the urinalysis results should not have been admitted as evidence.

The Court of Appeals was careful to make clear, however, that it was not holding that a supervised releasee always has the right to cross-examine a technician who tests a urine sample. The facts in Perez’s case were “unusual,” the Ninth Circuit noted. There was no other evidence offered to support the revocation, such as possession of illegal drugs or multiple urine samples that tested positive, for example.

Accordingly, the revocation of Perez’s supervised release was reversed. See: United States v. Perez, 526 F.3d 543 (9th Cir. 2008).

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Related legal case

United States v. Perez