updated 8:31 p.m. ET July 15, 2004

WASHINGTON - Researching a documentary on Jack Johnson, filmmaker Ken Burns decided that racism, not justice, sent the first black heavyweight boxing champion to jail nearly a century ago.

Burns decided to seek a presidential pardon to right the wrong. On Tuesday, civil rights leaders and Sens. John McCain and Orrin Hatch joined Burns to announce the filing of legal papers with the Justice Department seeking the pardon.

The petition argues that Johnson’s 1913 conviction under the Mann Act, a law passed three years earlier than bans the interstate transport of women for immoral purposes, unfairly punished him for a consensual relationship with a white woman.

“A gross and grave injustice was done to Jack Johnson where a law was perverted to send this decent American to jail,” said McCain, R-Ariz. “Pardoning Jack Johnson will serve as a historic testament of America’s resolve to live up to its noble ideals of justice and equality.”

Hatch, R-Utah, said: “This man was flamboyant. But there was a reason for the flamboyancy: he was taking on the world and fighting to give African-Americans a chance.”

Johnson died in a traffic accident in 1946 at age 68. If granted, the pardon would be only the second awarded posthumously. The first was President Clinton’s 1999 pardon of Henry O. Flipper, a former slave who became the first black army officer.

Johnson became the first black champion when he stopped Tommy Burns in Australia in 1908. Two years later, he defeated challenger Jim Jeffries, who had come out of retirement as the “Great White Hope” to beat the black man.

Johnson’s victory, in an era when Jim Crow laws and segregation ruled, sparked race riots in parts of the country. But it was not just the championship that made many white Americans hate him.

In a 1983 biography of Johnson, Randy Roberts wrote that the boxer was proud of his conquests among white women. Prosecutors moved against him in 1912 by arresting Johnson on the charge of abducting Lucille Cameron.

Johnson was indicted, but the government lost Cameron as a witness when she became the second white woman to marry Johnson; a wife cannot be forced to testify against her husband. The prosecution came up with a witness, Belle Schreiber, also white and a former mistress. Her testimony led to Johnson’s conviction, and he served a 10-month sentence.

The petition filed Tuesday contends the conviction was legally unfounded, the first trial in which the Mann Act was invoked to invade the privacy of consenting adults.

The district attorney at the time, Harry Parkin, called the conviction “the foremost example of the evil in permitting the intermarriage of whites and blacks,” which Burns’ petition said revealed the extreme prejudice at the time.

McCain and Hatch said they plan to ask other senators to join in a resolution urging that Johnson be pardoned. Other supporters include Sen. Edward Kennedy, D-Mass.; Rep. Jesse Jackson Jr., D-Ill.; boxers Sugar Ray Leonard and Vernon Forrest; and actor Samuel L. Jackson.

Burns’ documentary on Johnson, titled “Unforgiveable Blackness: The Rise and Fall of Jack Johnson,” will air on PBS in January.

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