For the last four years, federal probation offices have been authorized to use a new drug testing device, a patch worn on the body that absorbs and collects components of sweat, including drugs. Now in widespread use at US probation offices, the sweat patch, manufactured by PharmChem Laboratories of Menlo Park, California, was supposed to enhance law enforcement efforts to catch drug users.
But dogged federal defenders in Nevada, where the US probation office has used the patch since 1997, have blown a huge hole in its reliability. Fallout has so far been limited mainly to Nevada, but could spread across the US Court system. It could also scuttle PharmChem's grand vision of widespread adoption of the patch in the federal workplace.
Nevada defenders had for the past 2 1/2 years sought to challenge the patch in court after hearing repeated complaints from federal probationers who bitterly denied they were using drugs despite positive results from the patch.
Then, in dramatic testimony at a November 30th federal court hearing in Las Vegas, a prosecution witness unexpectedly bolstered the federal defenders' claim that the patch picks up environmental contaminants, thus causing false positive drug test results. The testimony has also prompted federal court officials in Nevada and the local US Attorney's Office to think again about relying on the patch.
At the hearing, in the case of a woman accused of violating the conditions of her release after the patch indicated she had used cocaine, PharmChem toxicologist James Meeker stunned prosecutors when he revealed that PharmChem's own in-house tests found evidence of external contamination.
Meeker described studies in which researchers placed a tiny amount of cocaine -- invisible to the naked eye -- on the skin of five subjects. Researchers then wiped the skin with isopropyl alcohol before applying the patch. Two of the five subjects tested positive for cocaine, Meeker testified. He also revealed that PharmChem was concerned enough about the patch's reliability that it contracted with an independent lab to conduct further tests.
Although Meeker testified that he still believed the patch "is acceptable and reliable to determine drug use," the damage was already done. Within days of Meeker's testimony, prosecutors ended their effort to revoke the woman's release.
"We didn't want to be in a position where we were trying to revoke somebody based on science that wasn't sound," Assistant US Attorney Joseph Sullivan told the Las Vegas Review-Journal. "We decided to step back and see whether the potential for contamination is legitimate."
Then US probation officials in Nevada stepped in to announce that, in light of Meeker's testimony, they will no longer use patch test results as the sole basis for violating federal probationers or those on supervised release. Until the patch's reliability can be confirmed, US probation officers in Nevada will use other indicators of drug use, such as urine tests and eyewitness accounts to corroborate the patch.
"We think the sweat patch is a great drug detection device," said senior US probation officer Mike Severance. "The problem is it may be too good," he told the Review-Journal.
Meanwhile, concerns about the patch resulted in two more aborted revocation hearings. In mid-December, US probation officials in Las Vegas withdrew a revocation petition against a man whose patch came back positive for methamphetamines.
"We would now request that this petition be withdrawn due to new evidence shared with our office by PharmChem Laboratories which has shown the patch may have returned positive due to environmental contaminants," the prosecutors wrote in court documents.
And in an early sign of the potential national impact, federal prosecutors in Oakland late in December declined to proceed with a revocation hearing after learning of Meeker's testimony.
That's not enough for Franny Forsman, the head federal public defender for Nevada. "I think it should be pulled off the market until the problems are fixed," she told the Review-Journal. "This thing ought not to be used because it is being used in this city to take people's kids away and to put people in jail."
In addition to the federal courts, judges in the Clark County (Las Vegas) Family Courts have been using the patch when parents in custody battles make allegations of drug use.
The sweat patch is good business for PharmChem. In Nevada, probation official Severance told the Review-Journal, PharmChem gets $5 for each patch and $20 for each test. US probation officials in Nevada used 850 patches in 2000.
But PharmChem wants to get the patch into the federal workplace, where its potential customer base would be in the hundreds of thousands.
"If it gets into the workplace, it's a lucrative proposition for PharmChem," said Forsman, who spearheaded the campaign against the patch.
PharmChem may have to reevaluate its plans, though. Now, thanks to the efforts of Forsman and the Nevada federal defenders, the patch is fair game across the country.