Recreational marijuana is allowed in California and eight other states. Twenty other states allow only medical marijuana. And, of course, federal law still bans marijuana.
MAP: Where is weed legal?
That's why San Francisco International Airport on Friday tweeted a warning: "TSA screens for aviation threats, but also law violations. Federal law treats marijuana as illegal. Passengers with suspect items at checkpoints will be sent to law enforcement officer."
That may soon change.
On Friday, Senate Minority Leader Democrat Chuck Schumer announced on Twitter he's introducing legislation to decriminalize pot at the federal level.
"This means federal agents will not be arresting people, trying people for use of marijuana," Schumer said.
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Schumer's bill would also establish funding for women and minority-owned marijuana businesses and require more research on the health impact of cannabis.
Meantime, law enforcement agencies are asking Californians to use with "caution."
The Marin County Sheriff's Office tweeted: "Happy April 20th! For those that celebrate 420, please be wise about your celebration and designate a sober driver or use a ride share...just like alcohol, driving impaired is dangerous and against the law."
Penalties and fines are anywhere from $390 to $1,000.
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Happy April 20th! For those that celebrate 420✌🏼, please be wise about your celebration and designate a sober 😷 driver or use a ride share. Just like alcohol driving impaired is dangerous and against the law. #DriveSober #BeSafe pic.twitter.com/F49bjhd8aM— Marin County Sheriff (@MarinSheriff) April 20, 2018
The time has come to decriminalize marijuana. My thinking – as well as the general population’s views – on the issue has evolved, and so I believe there’s no better time than the present to get this done. pic.twitter.com/EIHgsI8j6C— Chuck Schumer (@SenSchumer) April 20, 2018