SAN FRANCISCO — California’s medical marijuana law survived its most serious legal challenge today as the U.S. Supreme Court denied appeals by two counties that argued they were being forced to condone violations of federal drug laws. The justices, without comment, denied a hearing to officials from San Diego and San Bernardino counties who challenged Proposition 215, an initiative approved by state voters in 1996 that became a model for laws in 12 other states. It allows patients to use marijuana for medical conditions with their doctor’s recommendation. The counties specifically objected to legislation requiring them to issue identification cards that protect holders from arrest by state or local police for possessing small amounts of marijuana for medical use. The U.S. Supreme Court has ruled that the federal government can enforce its laws against marijuana to prosecute users and suppliers of the drug in California and the other 12 states. The Obama administration has said it will target only traffickers who violate state as well as federal laws, although it has not stopped U.S. attorneys from raiding dispensaries that operate with local government approval. Prop. 215 remains in effect despite federal enforcement efforts that began as […]