A test that is not coincident with the discovery of the alleged drug useage may violate the employee's privacy rights under the California Constitution, Art. 1, Sec. 1.
"The primary focus of a state constitutional privacy claim in the employee drug testing context is a reasonable balancing test--balancing the drug test's intrusion on the reasonable expectations of the employee against the drug test's promotion of the employer's legitimate interests." Kraslawsky v. Upper Deck Co. (1997) 56 Cal.App.4th 179, 186-187, 65 Cal.Rptr.2d 297, 301 (emphasis added).
The point here is that an employee whose actual work is unaffected by the alleged drug use, and the absence of any substance-abuse safety issues (e.g., employee is a health care professional, lifeguard, figherfighter, peace officer, commercial driver, railroad engineer, nuclear engineer, power plant engineer, crane operator, etc.) wil almost certainly weigh in favor of the employee. Whereas, an employee who is involved in employment where safety issues are of concern, will weigh in favor of the employer.
There's no bright-line test here. The employer must determine whether the test is "business related and consistent with job necessity." 2 USCA § 12113(c).
I wish I could give you a clear "yes" or "no." However, your facts suggest that this may be difficult under the circumstances.
Hope this helps.
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