Washington • Continuing to draw on his clemency powers, President Donald Trump said Friday that he may soon pardon Muhammad Ali — a sentiment that a lawyer for the late boxer quickly said was appreciated but unnecessary.

Ali was convicted in 1967 for refusing to report for induction into the United States military during the Vietnam War. His local draft board rejected his application for conscientious objector classification.

“He was, look, he was not very popular then, certainly his memory is popular now,” Trump told reporters as he prepared to leave the White House on Friday en route to a Group of Seven economic summit in Canada.

Trump said he was thinking “very seriously” about pardoning Ali as well as other “folks that have some sentences that aren’t fair.”

But Ron Tweel, an attorney for Ali, who died in 2016, pointed out that the U.S. Supreme Court overturned Ali’s conviction in 1971. In a unanimous ruling, the court found that the Department of Justice had improperly told the draft board that Ali’s stance was not motivated by his Muslim religious beliefs.

That notion was echoed by Walter Dellinger, a professor at Duke University School of Law and an acting solicitor general during the Clinton administration.

“There is nothing to pardon!” Dellinger wrote on Twitter.

Trump’s musing about an Ali pardon was blasted by the Rev. Al Sharpton, who accused the president of “nothing more than grandstanding.”

Besides criticizing Trump for offering something unnecessary, Sharpton said Trump’s past “anti-Muslim and Islamophobic policies and rhetoric” were an affront to Ali’s religion.

“You can’t stand up for Islam while simultaneously denigrating it,” Sharpton said.

Trump has used his clemency powers to pardon or commute sentences in a string of high-profile cases recently. Those have included the late Jack Johnson, the first black heavyweight boxing champ, whose posthumous pardon was championed by actor Sylvester Stallone, among others.

Trump told reporters Friday that his administration is “looking at literally thousands of names of people that have come to our attention that have been treated unfairly or where their sentence is far too long.”

He also said that he is open to hearing recommendations from NFL players and other athletes, arguing it was a better outlet for their concerns about racial injustice than taking a knee when the national anthem is played.

“I’m going to ask them to recommend to me people that were unfairly treated, friends of theirs or people that they know about, and I’m going to take a look at those applications,” Trump said. “And if I find and my committee finds that they’re unfairly treated, then we will pardon them or at least let them out.”

A pardon does not technically erase a conviction; it is an expression of forgiveness from the president that, in most cases, serves to undo the punishment and help the recipient of the pardon restore rights, such as the right to vote.

A posthumous pardon — as would be the case with Ali — is completely symbolic. While a pardon is typically not meant to imply innocence, that is perhaps the signal Trump is trying to send.

Last week, Trump told reporters he is considering pardoning lifestyle maven Martha Stewart, who was convicted in 2004 of obstructing justice and lying to investigators about a well-timed stock sale, and commuting the sentence of former Illinois governor Rod Blagojevich, D, who was convicted in 2010 of trying to sell the Senate seat vacated by President Barack Obama, among other campaign finance violations.

Those who have already received pardons from Trump include Joe Arpaio, the former sheriff of Maricopa County, Arizona, who was held in criminal contempt for ignoring a court order related to the detention of people suspected of being in the country illegally; and Dinesh D’Souza, a conservative commentator and filmmaker convicted of violating a campaign finance law.

Earlier this week, Trump commuted the sentence of Alice Marie Johnson, a woman serving a life term for nonviolent drug-related offenses, after meeting with reality television star and socialite Kim Kardashian West to discuss the case.

“The power to pardon is a beautiful thing,” Trump told reporters Friday. “I want to do people who are unfairly treated like Alice.”

The Washington Post’s Matt Zapotosky contributed to this report.