Can we conduct in-house drug testing?

Yes, employers can conduct drug tests on site but should be aware of a few issues.

First, you must have a clear, written policy that upon reasonable suspicion of illegal (or legal) drug usage, the company will be conducting drug testing.

Supervisors need to be trained on the signs and symptoms of usage, and to know what to do when they observe these signs. The mere observation of someone “acting funny” doesn’t support the need for testing. Even researching signs on the internet can help your people learn what to look for.

Second, with in-house testing, testing can be done immediately, or even in the middle of the night, for a warehouse setting, for example, when outside labs are generally closed. Nevertheless, if an employee tests positive for drugs, it is wise to send them for a second, confirming test at a professional lab. If the employee is terminated due to the test results, it is easier to challenge an in-house test versus a professional lab.

A professional lab will test the sample with techniques that are highly accurate and can help rule out any false positives that the employer might have gotten.

Additionally, effective January 1, 2024, California prohibits discrimination on the basis of an applicant’s or employee’s off site and off-duty use of cannabis. Employees may still conduct testing for cannabis, but the test must be a valid screening conducted through methods that do not screen for nonpsychoactive cannabis metabolites. Employers using drug testing should work with their legal counsel and testing supplier/vendor to ensure they are in compliance with California law.

Lastly, it is important to keep the results confidential. Said results are protected under the California Confidentiality of Medical Information Act and the Health Insurance Portability and Accountability Act (HIPAA) privacy laws, and should be kept in a separate, confidential medical file.

Read more about When Drug Testing May Be Permitted in the HR Library.