SALT LAKE CITY — A legal challenge to the medical marijuana compromise bill that Utah lawmakers passed last year will now take place in federal court.

State attorneys say the amended lawsuit the Epilepsy Association of Utah and Together for Responsible Use and Cannabis Education filed in state court earlier this month raises for the first time issues that are a matter of federal law.

The groups sued the state last December after the Utah Legislature passed a bill to replace voter-approved Proposition 2 legalizing medical marijuana in the state.

The amended complaint claims lawmakers violated voters' constitutional rights and passed directives that conflict with federal law, which still considers marijuana an illegal drug. The recrafted argument came after the state contended in court filings that legislators have the authority to change the law.