Warning: Even if medical marijuana is legal in your state and you have a valid prescription, your employer can still fire you for using it. A Michigan man learned this the hard way after failing a drug test given by his employer of five years, Walmart.

Joseph Casias has cancer and a brain tumor, and has a marijuana prescription to help him deal with his chronic pain. He claims that he never came to work under the influence, but the company’s policies are strict–and apply even where pot is legal for medical use.

[L]ast November, Casias sprained his knee at work. Marijuana was detected in his system during the routine drug screening that follows all workplace injuries. Casias showed WalMart managers his state medical marijuana card, but he was fired anyway.

“I was told they do not accept or honor my medical marijuana card,” says Casias.

In an e-mail from headquarters, WalMart spokesman Greg Rossiter explained the company policy. It states: “In states, such as Michigan, where prescriptions for marijuana can be obtained, an employer can still enforce a policy that requires termination of employment following a positive drug screen. We believe our policy complies with the law and we support decisions based on the policy.”

Walmart is challenging his claim for unemployment benefits, which he has collected since November.

Walmart fires Michigan man for using medical marijuana [WZZM] (Thanks, Carol!)

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