Congressional backers of a pardon for Jack Johnson, the world's first black heavyweight champion who was imprisoned nearly a century ago for his romantic relationships with white women, say his prosecution was racially motivated. Johnson made the same argument 90 years ago while in prison, records at the National Archives show.

In a March 25, 1921 letter to Attorney General Harry Daugherty, Johnson said the prosecutor in his trial made "flagrant appeals to passion, race hatred and moral infamies."

During his 10 months in prison, Johnson sought parole, filed an application with the president seeking clemency, and wrote letters to the attorney general seeking early release. And he almost pulled it off, even though this was at the height of the Jim Crow era. Daugherty publicly raised the possibility of letting Johnson out a couple of weeks early, before announcing on June 28, 1921 — 90 years ago Tuesday — that Johnson would have to complete his sentence.

Now, under a black president and black attorney general, the Justice Department is against pardoning Johnson. In the last session of Congress, both houses of Congress passed a resolution urging a pardon pushed by Sen. John McCain, R-Ariz., and Rep. Peter King, R-N.Y., "to expunge a racially motivated abuse of the prosecutorial authority of the federal government." But President Barack Obama has not acted on it.

While Obama hasn't commented publicly on the matter, the Justice Department's pardon attorney told McCain and King that the DOJ's resources are best used for pardoning the living. Still, the lawmakers are making another run at the pardon this year.

On June 23, 1921, The Associated Press reported that Daugherty was considering a pardon for the boxer in time for a heavyweight fight between Jack Dempsey and Georges Carpentier the following month. Eyeing a comeback, Johnson wanted to attend the fight, which would become the first $1 million gate in boxing history.

"Mr. Daugherty said Johnson had been a model prisoner and a 'liberty bonus' has been suggested," the story reported. "The Attorney General declared he would not consider pardoning Johnson to enable him to attend the championship fight, but that, of course, if any clemency was extended, Johnson's time would be his own."

But he changed his tune five days later. According to an AP account, the AG said that "considering the crime he did not feel that the parole privileges should be extended merely to allow Johnson to witness the world's title fight Saturday," even though he had said just a few days earlier that wasn't the reason he was considering letting Johnson out.

Johnson was hated by many white Americans, especially after retaining his title by defeating white boxer Jim Jeffries in the 1910 "Fight of the Century." Jeffries had come out of retirement for the bout, and Johnson's victory infuriated whites, setting off deadly race riots across the country.

Three years later, Johnson was convicted of violating the Mann Act, which made it illegal to transport women across state lines for immoral purposes. But the flamboyant boxer's real crime had been flaunting white society by having romantic relationships with white women.

Authorities first targeted his relationship with Lucille Cameron, who later became his wife, but she refused to cooperate. They then turned to Johnson's former mistress, a prostitute named Belle Schreiber, to testify that Johnson had paid her train fare from Pittsburgh to Chicago, for immoral purposes. An all-white jury convicted Johnson in 1913, and he skipped bail and fled the country. But in 1920 Johnson agreed to return and serve his sentence.

The National Archives records show that Daughtery's suggestion for letting Johnson out of prison early provoked some angry responses from people rushing to defend the honor of white women.

A handwritten letter dated June 25, 1921, with a copy of the AP story attached, asked the attorney general: "Would you insult the women (of the U.S.) by pardoning this man? Do you know his crimes against white women? Why this clemency towards the despoiler of homes? Disgusting." It's signed by "three white ladies," with the word "ladies" underlined five times.

"Why pardon the negro Johnson who should have 50 years in prison for his crimes against white women," asked Mrs. Tillie Schmidt, in a handwritten note. "I voted Republican ticket for the first time last March, but not any more if white women are not respected."

Still, some wrote the attorney general in support of releasing Johnson. On June 25, Daugherty received a petition from a group of people claiming to represent several hundred others asking that Johnson's sentence be commuted, and a couple of other letters expressed support as well.

In January of that year, a parole board had recommended approving Johnson's application for parole. But the Democratic attorney general, A. Mitchell Palmer, denied it.

Soon after, Johnson filed an "application for executive clemency" with the president (it was dated Feb. 19, 1921, when Democrat Woodrow Wilson was president, but not received at the pardon attorney's office until March 28, 1921, by which time Republican Warren G. Harding had moved into the White House). Johnson states in the application that he gave Schreiber money to help her out, and didn't know what she was going to do with it. "She merely said she was in bad straits and needed some money," he wrote, adding that imprisonment had taken a toll on his finances as well, to the tune of more than $200,000.

That March, he also sent two letters to Daugherty, who had replaced Mitchell as attorney general as part of the GOP administration, pleading for his freedom. One of them mentioned the appeals to race hatred in his trial.

In the other, Johnson questioned the motives of the former AG in denying him parole: "I would like to know if my being a black man would have anything to do with the action of Mr. Mitchell. I would like to know if my being a pugilist has had anything to with the denial of the application ... I am up a tree as to why I should be denied and other men released, men whose criminal records are almost as black as the ace of spades."

But Johnson's efforts were for naught, and he was still in prison when Jack Dempsey knocked out Georges Carpentier at 1:16 of the fourth round in front of 80,183 fans on July 2. One week later, Johnson, 43, walked out of prison and told reporters he wanted to challenge Dempsey for the heavyweight title, brushing aside Dempsey's vow to fight only white boxers.

"It doesn't make any difference what Dempsey says about drawing the color line: the public wants Dempsey whipped," Johnson told reporters after his release. "And the public knows I am the one to do it."

But Johnson, who died in 1946, never got his shot at Dempsey.

In 2004, the Committee to Pardon Jack Johnson, launched by filmmaker Ken Burns and others, filed a petition with the Justice Department asking for a posthumous pardon, and McCain and King introduced their resolution. As Texas governor, George W. Bush had proclaimed Johnson's birthday "Jack Johnson Day" for five straight years in honor of the Galveston, Texas native, but the Bush administration never acted on the petition.

Supporters were sure they'd have better luck with Obama, who became the nation's first black president 100 years after Johnson became the first black heavyweight champion. But they're still waiting.