If you live in California, and you rely on medical marijuana, which is legal to use in the state, you can get fired from your job. Even if it's legally prescribed.

In another setback for California's ongoing battle with the Feds over medical pot use, the California Supreme Court on Thursday upheld a lower court ruling that a Sacramento telecommunications company's firing of a man who failed a company-ordered drug test was legal.

The employee, Gary Ross held a medical marijuana card authorizing him to use the drug to treat a back injury sustained while serving in the Air Force.

The company, Ragingwire, however, fired him, pointing to federal laws. In their brief, they said they rightfully fired Ross because all marijuana use is illegal under federal law, superceding the medical marijuana laws in California and 11 other states.

A majority of the justices agreed.

"No state law could completely legalize marijuana for medical purposes because the drug remains illegal under federal law," Justice Kathryn Werdegar wrote for the 5-2 majority.

Further, the state Supreme Court said the so-called Compassionate Use Act passed by California voters in 1996 had "nothing" to do with employment laws.

"Nothing in the text or history of the Compassionate Use Act suggests the voters intended the measure to address the respective rights and duties of employers and employees," Werdegar wrote.  "Under California law, an employer may require preemployment drug tests and take illegal drug use into consideration in making employment decisions."

Justice Joyce Kennard dissented attacking the majority's ruling in the dissent as "conspicuously lacking in compassion." Kennard said the ruling "disrespects" the California medical marijuana law, and said employers should be barred from firing workers who use medical marijuana as long as they continue to perform their jobs adequately.

The U.S. Supreme Court declared in 2005 that state medicinal marijuana laws don't protect users from prosecution. The Drug Enforcement Administration and other federal agencies have been actively shutting down major medical marijuana dispensaries throughout California over the last two years and charging their operators with felony distribution charges.

Ragingwire claimed it fired Ross because it feared it could be the target of a federal raid, among other reasons. Ross argued that medical marijuana users should receive the same workplace protection from discipline that employees with valid painkiller prescriptions do.

The non-profit marijuana advocacy group Americans for Safe Access, which represents Ross, estimates that 300,000 Americans use medical marijuana. The Oakland-based group said it has received hundreds of employee discrimination complaints in California since it began tracking the issue in 2005.

California voters legalized medicinal marijuana in 1996.