This is something that I was afraid would happen back when Colorado first legalized Marijuana. I had read that the federal government via the ATF would not allow people obtaining a state license to smoke Marijuana to own firearms. Despite medical marijuana laws in 44 states, cannabis is still illegal under federal law. The federal government regulates drugs through the Controlled Substances Act (CSA) (21 U.S.C. § 811), which does not recognize the difference between medical and recreational use of cannabis. When I first read about this possibility it was under the Obama administration, and I figured it would only be a matter of time before it would happen.
This never occurred under the Obama administration; however, it appears the officials in Hawaii have taken it upon themselves to invoke such a statue. The Honolulu Police Department is ordering medical marijuana cardholders to surrender their firearms within a 30-day window of time.
KITV reports that Honolulu police are doing this via letters to cardholders demanding they “surrender weapons, permits, and ammunition to HPD or to transfer ownership.”
You can read more here.