As the first recreational pot in more than a century began being sold legally in Massachusetts Tuesday, Rep. Joe Kennedy III (D-MA) reversed his previous position on the drug and called on Congress “to remove marijuana from the Controlled Substances Act (CSA) and legalize it at the federal level.”

Kennedy, who opposed Massachusetts’ 2016 ballot measure to legalize recreational cannabis, wrote in an op-ed in STAT, the medicine and life sciences website: “One thing is clear to me: Our federal policy on marijuana is badly broken, benefiting neither the elderly man suffering from cancer whom marijuana may help nor the young woman prone to substance use disorder whom it may harm.”

“The patchwork of inconsistent state laws compounds the dysfunction,” Kennedy continued. “Our federal government has ceded its responsibility — and authority — to thoughtfully regulate marijuana.”

The Boston Globe noted that in 2016, Kennedy said “I don’t think marijuana should be legalized,” and as recently as March, he told Vox’s Ezra Klein: “My views do not exactly line up with my own state, and it’s something that I’m struggling with.”

Kennedy addressed his concerns about abuse and addition in the STAT op-ed, but said the current state of federal cannabis prohibition “is hard to justify,” especially given the increasing number of states where the drug is currently legal in some form.

The congressman said that while his “concerns about the public health impact of marijuana remain,” legalization at the federal level “would restore the federal government’s ability to regulate a powerful new industry thoroughly and thoughtfully.”

“It would allow us to set packaging and advertising rules, so marketing can’t target kids,” he wrote. “It would help set labeling requirements and quality standards, so consumers know exactly what they’re buying. It would ensure that we can dedicate funding to encourage safe use and spread awareness about the risks of impaired driving. And it would create tax revenue for research on mental health effects, safe prescription drugs, and a reliable roadside test.”