Gavin Newsom, the former mayor of San Francisco who hopes to become California's Governor in 2018, hasn't been shy about his disgust with the White House, speaking out against GOP policies regarding LGBTQ folks on more than one occasion and donating the campaign cash he got from Donald Trump to immigration non-profits. And now the Lieutenant Governor is shaking a fist DC-ward yet again, this time over the administration's still-nascent crackdown on legal recreational marijuana use.

Newsom came out in favor of legal weed as his campaign began to ramp up, and was one of California's loudest voices in favor of the state's legalization measure, which was approved by voters last November. He was apparently as alarmed as the rest of us to hear White House Press Secretary Sean Spicer (who should never, ever be referred to as "Sean Sphincter") say last week that the Department of Justice would go after users of recreational marijuana, even in states like California where the substance has been legalized.

As previously reported, Spicer had this to say on the topic Thursday:

There’s two distinct issues here: medical marijuana and recreational marijuana. I think medical marijuana, I’ve said before, that the president understands the pain and suffering that many people go through, who are facing especially terminal diseases, and the comfort that some of these drugs, including medical marijuana, can bring to them. And that’s one that Congress, through a rider in [2014], put an appropriations bill saying that the Department of Justice wouldn’t be funded to go after those folks.

There’s a big difference between that and recreational marijuana. And I think that when you see something like the opioid addiction crisis blossoming in so many states around this country, the last thing we should be doing is encouraging people. There’s still a federal law that we need to abide by when it comes to recreational marijuana and other drugs of that nature.

By Friday, Newsom had penned a response to Spicer's vague statement on the topic, and sent it off to the White House with a CC to Attorney General Jeff Sessions.

Describing current federal pot laws as “draconian and prohibitionist," Newsom wrote that "The war on marijuana has failed. It did not, and will not, keep marijuana out of kids’ hands.”

“The government must not strip the legal and publicly supported industry of its business and hand it back to drug cartels and criminals. Dealers don’t card kids," wrote the father of four.

"I urge you and your administration to work in partnership with California and the other eight states that have legalized recreational marijuana for adult use in a way that will let us enforce our state laws that protect the public and our children, while targeting the bad actors.”

Responding to Spicer's remarks on the opioid addiction crisis, Newsom wrote that "marijuana is nothing like an opioid and there is no scientific evidence that marijuana use increases the use of opioids.”

“Unlike marijuana, opioids represent an addictive and harmful substance, and I would welcome your administration’s focused efforts on tacking this particular public health crisis,” he wrote. “We can’t continue to keep doing what we’ve done and expect a different result. A tightly regulated marketplace for adult recreational marijuana use is a new and better approach.”

You can read Newsom's full letter below:

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