Canadian-born singer Neil Young says his plans to become a U.S. citizen and vote in the 2020 presidential election have been stymied because he smokes marijuana.

In a letter to his fans, the rock legend explained that he had recently applied to become a dual citizen and passed the test for American citizenship, answering honestly to each question. But, Young wrote Friday, he was asked to take another test “due to my use of marijuana and how some people who smoke it have exhibited a problem.”

Young said that problem stems from an April 19 clarification to U.S. Citizenship and Immigration Services policy that lists the use of marijuana, among other federally controlled substances, as a conditional bar to establishing “good moral character.”

Good moral character, or GMC, is a general requirement for U.S. citizenship introduced in 1970 that gauges whether an applicant “measures up to the standards of average citizens of the community in which the applicant resides.” Even though a number of U.S. states have decriminalized marijuana use for both medicinal and nonmedicinal purposes, the drug remains a controlled substance at the federal level.

Young, who turns 74 on Tuesday, specifically cited former attorney general Jeff Sessions in his letter, who in 2018 made it easier for U.S. prosecutors to enforce federal marijuana law in states that had legalized the substance. It came as a reversal to an Obama-era policy that discouraged enforcement of the law in states where it was legal.

The USCIS says U.S. citizenship applicants “involved in certain marijuana related activities may lack GMC if found to have violated federal law, even if such activity is not unlawful under applicable states and foreign laws.”

In a statement, a USCIS spokesperson said the agency could not discuss, confirm or deny information about Young’s case due to privacy protections. The spokesperson reiterated that marijuana remains illegal under federal law as a Schedule I controlled substance.

The District of Columbia and 11 states — Alaska, California, Colorado, Illinois, Maine, Massachusetts, Michigan, Nevada, Oregon, Vermont and Washington — have adopted laws allowing recreational use of the drug.

“I sincerely hope I have exhibited good moral character and will be able to vote my conscience on Donald J. Trump and his fellow American candidates, (as yet unnamed),” Young wrote on his website. “I will keep you posted, but I don’t think I will be able to remain parked here during the proceedings.”

In an interview with the Los Angeles Times last month, Young said even though he moved to California in the mid-1960s, the country’s climate crisis is a prevailing reason he wants to become a U.S. citizen now. A known liberal and environmentalist, Young in 2015 asked Trump not to use his song “Rockin’ in the Free World” at campaign events.

“We’ve got a climate emergency and governments are not acting. Democracy is based on [the principle that] you have a vote, you have a voice,” he told the Times. “I’m still a Canadian. There’s nothing that can take that away from me. But I live down here. I pay taxes down here. My beautiful family is down here. They’re all Americans. So I want to register my opinion.”

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