“Yes, there are laws on the books that say one thing, but that is perhaps why the pardon power exists – for the exceptions, for the things that may seem unlawful in letters on a page but when we look at them morally, when we look at them ethically, when we look at the results, it seems these were necessary things, these were vital things,” Snowden said in Moscow.

Obama has given few pardons during his presidency, instead focusing his constitutional clemency power on commutations for drug offenders who he says received disproportionately long sentence as part of a decades-long “war on drugs.” And in response to a question last month, Obama said he would not follow the practice of past presidents in granting last-minute, politically motivated pardons, instead requiring all pardons to go through the formal Department of Justice process.

On that basis, Snowden appears ineligible for a presidential pardon. While presidents can pardon people not convicted of a crime — President Gerald Ford pardoned President Richard Nixon, after all — the Obama administration guidelines require an applicant to wait five years after a conviction and pass an FBI background check, a process that can take years to complete.

But Snowden’s attorney said that position is a cop out. “The constitution didn’t assign this power to the Department of Justice. It assigned it to the president,” said Ben Wizner. “I would hope that President Obama would like to resolve this situation on his watch.”

As of Monday, the White House position appeared unchanged.

“Mr Snowden has been charged with serious crimes, and it’s the policy of the administration that Mr Snowden should return to the United States and face those charges,” White House Press Secretary Josh Earnest said. “He, of course, will be afforded due process, and there are mechanisms in our criminal justice system to ensure that he’s treated fairly and consistent with the law. And that’s what the president believes.”

Wizner, a lawyer with the American Civil Liberties Union, said he’s realistic about the chances for an Obama pardon, but the pardon campaign is part of a long-term strategy to convince US policymakers that Snowden’s revelations were in the public interest.

That argument was bolstered by no less a figure than former Obama attorney general Eric Holder, who said in May that Snowden “performed a public service by raising the debate” on government surveillance.

Snowden’s request for a pardon also comes as the Oliver Stone movie Snowden appears in theaters this weekend.

“The president has said routinely to social change activists that if they want change, they should campaign for it,” Wizner said, “And that’s exactly what we intend to do.”