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DOT Rule 49 CFR Part 40 Section 40.149 Q&A

§40.149                                                                      09/01
Can arbitrators change or overturn the MRO’s determination about the verification of a test result?
• No. The MRO is the only person authorized to change a verified test result (see §40.149(c)). The MRO can do so with respect to a verification decision he or she has made, in the circumstances described in §40.149.
• An arbitrator is someone who derives his authority from the employer, or from a labor-management agreement. The arbitrator cannot exercise authority that the employer could not exercise on its own. The arbitrator could not overturn a decision of the MRO concerning a test verification any more than the employer could on its own.
• This prohibition applies to substantive decisions the MRO makes about the merits of a test (e.g., with respect to whether there is a legitimate medical explanation for a positive, adulterated, or substituted test result or whether a medical condition precluded an individual from providing a sufficient specimen).
• An arbitrator could determine that a test result should be cancelled because of a defect in the drug testing process involving the MRO (e.g., that the MRO failed to afford the employee the opportunity for a verification interview). But an arbitrator could not overturn the substantive judgment of the MRO about whether, for example, the information submitted by the employee constituted a legitimate medical explanation.

§40.149; §40.209                                                    09/01

What is an employer to do if an arbitrator’s decision claims to overturn the result of a DOT drug or alcohol test on grounds contrary to DOT regulations?
• There could be instances in which an arbitrator makes a decision that purports to cancel a DOT test for reasons that the DOT regulation does not recognize as valid.
• For example, the arbitrator might make a decision based on disagreement with an MRO’s judgment about a legitimate medical explanation (see §40.149) or on the basis of a procedural error that is not sufficient to cancel a test (see §40.209).
• Such a test result remains valid under DOT regulations, notwithstanding the arbitrator’s decision. Consequently, as a matter of Federal safety regulation, the employer must not return the employee to the performance of safety-sensitive functions until the employee has completed the return to duty process.
• The employer may still be bound to implement the personnel policy outcome of the arbitrator’s decision in such a case. This can result in hardship for the employer (e.g., being required to pay an individual at the same time as the Department’s rules prevent the individual from performing the duties of his job).