Jack Johnson’s great crime, in the words of W.E.B. Du Bois, was his “unforgivable blackness.”

And for that, Johnson, one of the greatest boxers of all time, was railroaded on trumped-up federal charges and locked away in prison for almost a year. White racist Americans couldn’t beat him in the boxing ring, as he defeated one “great white hope” after another, so they exacted their vengeance in a kangaroo court of law.

EDITORIAL

This was during the lynching era, to be sure. In the year Johnson was imprisoned, 1920, at least eight other African-American men were victims of racially motivated killings. But as we approach the 100th anniversary of this historic wrong against Johnson, our nation’s racial roiling continues still, creating a powerful argument for finally — if only symbolically — setting things right.

President Donald Trump tweeted last month that he’s considering granting a posthumous pardon to Johnson, at the urging of the actor Sylvester Stallone. We hope the president’s not feigning this time. We hope he follows through.

Let’s be blunt about Johnson’s failings as a man, black or white. President Barack Obama declined to pardon Johnson, and when his attorney general, Eric Holder, was pressed about why, Holder frankly admitted that Obama’s reluctance was entirely unrelated to Johnson’s wrongful conviction.

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Johnson was “convicted unfairly,” Holder said in 2016, but there are “countervailing concerns about the way he treated women, physically treated women. So all of this has to be balanced before this president or his successor would make a determination that a pardon is appropriate.”

To our thinking, the task for Trump is to pardon Johnson in such a way that makes this distinction clear — that the sole purpose is to reverse a historic racist injustice, and nothing more. A pardon need not, and must not, be seen as a kind of absolution for any other very real offense.

Johnson was convicted of taking a white girlfriend, whom he later married, across state lines. He was convicted under the Mann Act, a law meant to protect women against prostitution. The vaguely written law sometimes was used, as in Johnson’s case, simply to punish black men for the perceived sin of consorting with white women.

Johnson’s real offense was flouting conventions about a black man’s “place” in early 20th Century America. He dressed flashy, talked brashly, lived large and married three white women.

When a white cop once pulled him over for speeding and charged him $50, he gave the officer $100 and said it was payment in advance — because he was going to roar back later at the same speed.

Johnson, who died in 1946, is buried in Chicago’s Graceland Cemetery. Among those calling for his posthumous pardon are Sen. John McCain and the documentary filmmaker Ken Burns, whose two-part film about Johnson is titled “Unforgivable Blackness.”

A pardon for Johnson is only right and long overdue.

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