Lassen/APJoseph Casias, 30, who uses medical marijuana to treat symptoms of an inoperable brain tumor and cancer claims in a lawsuit that he was wrongfully fired from a Walmart store in Battle Creek, MI.

Joseph Casias might just feel like a dope for doping -- even though it was legal.

The Michigan father of two sued Walmart this week for firing him after he tested positive for marijuana -- which he was using to alleviate pain from a brain tumor and sinus cancer.

Casias, 30, was canned late last year after five years on the job in Battle Creek.

According to the complaint, Casias tested positive for marijuana in a drug test administered after he injured his knee at work, under a Walmart policy that requires employees injured on the job to take the test.

Casias, who won an associate of the year award at the store in 2008, has been using marijuana on his oncologist's advice after Michigan voters passed a law approving the drug's medical use in 2008.

“Joseph is an example of a patient for whom marijuana has had a life-changing positive effect,” the complaint states.

A Walmart spokesman said he sympathized with Casias, but defended the dismissal.

"Like other companies, we have to consider the overall safety of our customers and our associates, including Mr. Casias, when making a difficult decision like this,” said Greg Rossiter.

The American Civil Liberties Union also has filed a lawsuit against the nation’s largest retailer.

"No patient should be forced to choose between adequate pain relief and gainful employment," Scott Michelman, a staff attorney with the ACLU Drug Law Reform Project told CNN. “And no employer should be allowed to intrude upon private medical choices made by employees in consultation with their doctors.”

Michigan is an at-will employment state, which means employers can fire a worker for any reason unless it falls under a federally protected category such as race, gender and religion. The ACLU is arguing legal medical marijuana users also should be included.

According to the complaint, Casias wants to be rehired and is seeking compensatory and punitive damages.

Read more: http://www.nydailynews.com/news/national/2010/07/02/2010-07-02_walmart_fires_employee_for_using_medical_marijuana_in_michigan_worker_and_aclu_s.html#ixzz0scNuYyGx