An employee refused a drug test due to reasonable suspicion of substance use on site. A few days later, he got himself tested and gave us the results—negative, of course. Do we have to accept his test as meeting our own for-cause testing policy?
The only possible exception would be in the unlikely event that your drug testing policy lets employees do their own testing. But most testing policies give employers controlling over testing to ensure a fair and honest result. The other problem, of course, is timing. A negative result days later doesn’t prove the employee was clean at the time of the reasonable suspicion triggering on-site testing.
Caveat: Be sure you did actually have reasonable suspicion and followed the testing procedures your policy requires. If you did, you very likely have grounds to discipline the employee for refusing to submit to testing at the time as your policy requires.