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Drug screening for the courts
The good, the bad and the ugly
by Mike Grosh and Steve Barber
Jun 15, 2003
A state caseworker once told us, "We watch the levels of cocaine over time, and as long as they generally keep going down for a month or so, we can tell the court that the client is making progress." Little did this caseworker know that cocaine is not detectable in urine after three days. His client, who tested positive five days after the initial positive test, had re-used in the interim, but the court was given wrong information.

Similarly a Judge told us he uses the reported levels of canabanoide (Marijuana) in a similar fashion- if levels are going down testee is abstaining. Levels are a function of a number of factors including diet, fluid intake, exercise, and others. Levels can fluctuate up or down with continuous use. When I informed the Judge that the method he was using was invalid he replied, "I know, but what else is there? In fact, there is a technology that will measure recent marijuana use without reporting positive for previous use. It's called oral fluids testing. Few people in the court system are aware of oral fluid testing and those that are often are misinformed about its accuracy.

Then there was the Referee who insisted on a Breathalyzer test rather than a urine alcohol screen for a client who was proscribed from ingesting alcohol--then gave him 24 hours to comply. The Referee apparently did not know that the presence of alcohol can be detected in urine long after it can be detected through the use of a breathalyzer. And in any event, alcohol in urine is undetectable by any technology after 24 hours.

There was also the case of the judge who ordered a hair screen, testing for "all substances" on an individual. The judge was not aware that it is only possible to test for five specific substances through hair screening, nor did he realize that any type of test for "all substances" would cost the state many thousands of dollars.

Courts are in the business of seeking truth. Attorneys, and those who are charged with providing evidence or testimony to the court are obligated to provide good information. Drug screen results provide accurate data, but unless the appropriate technology is used and the analysis of resulting data is on target, bad decisions can result. We hope that this article will shed light on some common misconceptions, and provide impetus for additional education in this critical forensic area.


Let's start by reviewing the kinds of technologies available to the courts today:

  • Urine screen--probably the oldest technology and the one with which courts are most familiar. Urine screens can find many substances not yet detectable by other methodologies. It also enjoys precedent and nationally recognized testing standards. Urine testing is by far the most evidentiary option. But what kind of urine testing? If it is lab-based testing, what methodologies are employed by the labs, it the lab certified, and to what standards does the testing subscribe? Urine testing has some limitations. For example, the detection window (except marijuana) is typically only one to three days. Urine testing is also relatively easy to compromise unless the testing is "observed.

  • Hair testing is a newer technology gaining increasing acceptance. It has several advantages. For example, it has the longest detection window--it will determine use for up to three months prior to testing. Collection for hair screening is non-invasive, and always observed without any invasion of privacy. That said, hair testing has its limitations too. It only tests for 5 substances--marijuana, cocaine, opiates, PCP and amphetamines, and it is about twice the cost of lab-based urine testing. Also, though unsubstantiated scientifically, some claim an inherent racial prejudice with hair testing.

  • Oral fluids testing is also a relatively new technology. As with hair testing, collection is observable with no privacy invasion. Oral fluids testing can check for recent marijuana use in a chronic user--something that urine and hair screening cannot do. And, the accuracy of the method has been thoroughly evaluated by the scientific community, so much so that the Department of Transportation has indicated it will allow Oral Fluids testing as an alternative to urine testing for individuals under its regulation. Oral fluids testing is no more expensive than urine. All that considered, oral fluids does not yet enjoy the precedence of urine and therefore may not be as universally accepted by the courts.

  • Patch testing is yet another new technology. Patch testing measures future use--from the time the patch is applied until the time the patch is removed. It will detect any use of amphetamines, opiates, cocaine, PCP, and marijuana. It will not, however, measure any use prior to application. It must be applied and removed by specially trained collectors. Also, anecdotal evidence indicates patches are easily compromised. Like hair and oral testing, there is little case law regarding challenges to testing results.

  • "Instant tests" are either urine or oral fluid-based, are generally inexpensive, and test for a variety of substances. Instant results take about 10 minutes to process. When combined with GCMS Confirmation testing of prospective positives their accuracy is about the same as their lab-based counterparts. However, care must be taken in the collection to insure that chain of custody documentation is complete and specimens are properly handled. Since there is no professional component in the initial testing and no separation from the collectors and the testing agency, instant tests are often viewed as less evidentiary that lab-based testing.

  • Urine alcohol vs. blood alcohol vs. breathalyzers. Alcohol leaves the body rapidly. No technology is good enough to measure it after 24 hours, although some is on the horizon. Blood and breathalyzers are the technology of choice for measuring for intoxication, but testing should be accomplished promptly. Urine alcohol testing, although having a longer detection window, is still only valid for 6 to 24 hours. Urine alcohol should never be used to determine intoxication, but is the technology of choice for simple alcohol use.

The importance of confirmations

All SAMSHA Certified laboratories strongly recommend that prospective positive results be followed up by GCMS Confirmations. DOT, FAA, and other federal agencies require it on all tests performed under their regulations. During the confirmation process, a second sample of the original specimen is put through a different, more sensitive and specific form of analysis. Only when that test confirms the original positive result, will the lab call the specimen "positive." A small, but measurable percentage of specimens originally tested as "positive" will be relabeled "negative" after GCMS confirmation testing. Some labs will perform a second test with the same or similar technology. That approach merely duplicates the original margin of error. GCMS testing is considered the gold standard, with an unimpeachable record of accuracy.

The MRO (Medical Review Officer)

How do you find out the meaning of "levels" in your determinations? What about "other" classifications--dilute, temp out of range, adulterated, substituted? What if the individual testing positive claims to have a prescription that caused the positive? Did he or she have the prescription? If so, did the prescribed medication cause the positive? Is he or she abusing the prescribed drug? A MRO can sort out all the issue giving additional accuracy and credibility to drug testing results. When in doubt, use a MRO (Medical Review Officer). These individuals are licensed physicians with additional training and certification in substance abuse issues.

If you are like many people first encountering the complexity of drug screening, this article probably has produced more questions than answers. It should. There is much to consider about drug testing. What should you test for? Many test only for marijuana, cocaine and, perhaps, opiates, but there are many other drugs of abuse, both prescription and non-prescription, that contribute to the problem. What technology should be used in a given situation? Where are collection done? Which laboratory should be used? And, to complicate matters more, each case is unique, requiring choices specific to that situation, not a one size fits all policy. By far the greatest cause of error in the use and interpretation of drug testing is the sometimes-glib assumption of expertise where little or none exists. Like the saying goes, a little knowledge can be very dangerous. In the case of court related drug testing it can lead to serious injustice.

Who should do your testing?

Strictly speaking, except for "instant tests" with no confirmation, only laboratories do the actual specimen testing. Collection of the specimen can occur at a laboratory-affiliated collection site, a medical clinic, or in on-site locations. A laboratory, a clinic or a Third Party Administrator (TPA) can help with your testing program.
  • Clinics--can arrange laboratory tests. They are patient-oriented and employ knowledgeable collectors. Most are not familiar with forensic guidelines for collection of specimens and are often inflexible regarding billing and reporting.

  • Labs. For the most reliable service and most accurate results, you should always insist on dealing with a SAMSHA Certified laboratory. At the same time, they tend to be large, and therefore are often unwilling or unable to provide the personal service and special handling so many court-related screenings require.

  • Third party organizations--often have agreements with multiple laboratories and multiple collection sites; can help design testing programs, can secure the best pricing, can provide access to, labs, collection sites, MRO, professional witnesses, and be helpful in the selection of appropriate testing protocols, and can often arrange personnel for instant test collection.

copyright 2008 Span Corporation Mike Grosh is President, and Steve Barber is Director of Testing Service for Span Corporation, a national provider of drug screen and background investigation Third Party Administration services. Span Corporation headquarters are located at 1505 White St Ann Arbor MI 48103. Mike, Steve and Span Corporation can be reached at 734-623-7726 or Website URL:

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Revision History #
  • v1.0 - Jun 15, 2003 - Authors - Original version.
  • v1.1 - Apr 1, 2008 - Erowid - Html'd and published on