False Positive Drug Test on Probation in Texas

Step 1: identify the actual claim

Before you do anything else, identify which type of dispute you have:

• Cross-reactivity dispute: The screening test picked up a substance that wasn't really the controlled drug — common with poppy seeds, certain SSRIs (amphetamines), CBD products (THC). Confirmation testing usually resolves this, but the resolution is sometimes wrong.
• Prescription dispute: The substance was real but lawfully prescribed (e.g., Adderall confirmed as amphetamine; confirmed as ). The result is technically positive but the use was lawful.
• Chain of custody dispute: The sample handling, identification, or testing process has a documented error that makes the result unreliable.
• Specimen validity dispute: The lab's own validity testing flagged the sample as suspect (high or low specific gravity, abnormal pH, low creatinine).
• Lab error dispute: The confirmation test itself produced the wrong result due to instrument malfunction or operator error — rare but documented.

Step 2: request the full lab report immediately

Most probation officers present a summary positive report, not the full document. You have a right to the complete chain-of-custody form, screening result with cutoff, confirmation result with cutoff, and specimen validity testing.

Send a written request to the probation officer (and CC counsel) within 24-48 hours of being notified of the positive result. Specify:

• Chain-of-custody form (CCF)
• Initial screening immunoassay report
• Confirmation testing report (GC-MS or LC-MS)
• Specimen validity report
• Lab's confirmation cutoff levels
• Operator and analyst credentials

If the lab fails to produce these on request, the result itself becomes harder for the prosecution to authenticate at a revocation hearing.

Step 3: request a split-specimen retest

SAMHSA-compliant collection produces two specimens — Bottle A (tested) and Bottle B (sealed for retest). You have a right to request testing of Bottle B at a different SAMHSA-certified lab. Cost varies ($75-300); some probation programs cover it, most require the probationer to pay.

Bottle B retest is most useful when:

• The original confirmation is borderline (just above cutoff)
• Specimen validity was questionable
• Chain of custody has gaps
• You have a credible alternative explanation (prescription, cross-reactivity, contamination)

It is not useful when the original result is deeply positive and your dispute is "I didn't use" without alternative explanation — retest will almost certainly confirm.

Step 4: document the alternative explanation

If your dispute rests on prescription medication, lawful exposure, or other innocent cause, document it with hard evidence:

• Prescription dispute: Pharmacy records showing the prescription fill dates and dosages; treating physician letter confirming current treatment
• Food/contamination dispute: Receipts, photos, witness statements; for poppy seed claims, specific identification of the product consumed
• Passive exposure dispute: Witness statements identifying when and where exposure occurred; comparative testing within a few days of the original test
• Industrial/workplace exposure: Employer documentation of substance handling; OSHA exposure records

"I don't know how it got there" is rarely a winning argument. Specific, documented explanations move the needle.

Step 5: present at the revocation hearing — or before

Where possible, resolve disputes administratively before they become formal court matters. Probation officers and supervisors will sometimes void a positive UA with sufficient documentation. This avoids a Motion to Revoke filing entirely.

When the dispute escalates to a hearing, presentation matters:

1. Lab expert testimony: A toxicologist or forensic chemist can explain cross-reactivity, retest results, or chain-of-custody issues to the judge
2. Medical records and prescription documentation entered as exhibits
3. Cross-examination of the probation officer on retest requests, lab communications, and the officer's familiarity with the testing science
4. Comparison testing: Independent UA at a similar time can support claims of clean status

The state's burden at a revocation hearing is preponderance of the evidence — lower than beyond a reasonable doubt — but credible disputes still produce continued-probation outcomes.