I'm not familiar with WA law in particular, but I'm not aware of any laws that require an employer to offer rehab. If your employees have a contract, and the contract states otherwise, then of course that would control. Similarly, if you have a "past practice" of offering all "positive" employees rehab, it would be in your interest to do so again here to avoid any "discrimination" claims.
If you're unsure about what to do, I would consult with a local attorney. It may come down to practical considerations, rather than legal (do you want to keep the employee or give him or her another chance? does the job involve a lot of heavy machinery or other safety-related aspects? do you have any indication that the employee was actually under the influence at work?).
No attorney-client relationship is created, or intended to be created, by this answer. You should contact an attorney licensed to practice law in your State for assistance in analyzing your specific situation.
I would say it depends on what kind of business you operate. For example, if your business is subject to federal regulations, there are quite detailed drug/alcohol policies and procedures that need to be followed. However, if you business is not subject to such requirements, then you are not likely to be required to offer rehab. I would need more information about your business to give you a more definitive answer.
This answer is for general informational purposes only. An attorney client relationship does not exist as a result of the answer given.
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