WASHINGTON -LRB- CNN -RRB- -- The White House refused to indicate Monday whether President Obama will issue a posthumous pardon for Jack Johnson , the African-American boxing champion convicted in 1913 for dating a white woman . Jack Johnson 's 1910 defeat of Jim Jeffries , the `` Great White Hope , '' sparked riots . The House of Representatives on July 29 unanimously passed a resolution urging Obama to grant a pardon ; the Senate passed a similar measure by a voice vote on June 24 . The push for a rare posthumous pardon has been spearheaded for years by Sen. John McCain , R-Arizona , and Rep. Peter King , R-New York , two of Congress ' top boxing enthusiasts . `` It is our hope that you will be eager to agree to right this wrong and erase an act of racism that sent an American citizen to prison , '' they wrote Friday in a letter to Obama . Johnson , the first African-American to win the heavyweight title , was convicted for violating the Mann Act , which outlawed the transportation of women across state lines for `` immoral '' purposes . He served 10 months in prison on charges `` brought forward clearly to keep him away from the boxing ring , where he continued to defeat his white opponents , '' McCain and King said . Almost a century after Johnson 's conviction , his compelling saga has continued to capture the interest of sports writers , civil rights activists and historians . It provides , they agree , a unique window into American politics and culture at a time when Jim Crow-style racism reigned supreme . Johnson was first arrested for breaking the Mann Act in 1912 , four years after winning the heavyweight crown . That case fell apart , but investigators soon after charged him with a similar offense involving a woman he had dated years earlier . Justice Department lawyers argued it was a `` crime against nature '' for him to have a sexual relationship with a white woman . Judge Kenesaw Mountain Landis , later to become the first commissioner of Major League Baseball , set Johnson 's bail at $ 30,000 , the equivalent of more than $ 660,000 today . When a bail bondsman showed up , Landis jailed him , too , according to an account that filmmaker Ken Burns relays in his documentary `` Unforgivable Blackness : The Rise and Fall of Jack Johnson . '' An all-white jury convicted Johnson in less than two hours . `` Mr. Johnson was perhaps persecuted as an individual , but ... it was his misfortune to be the foremost example of the evil in permitting the intermarriage of whites and blacks , '' one of the prosecutors later said . Johnson 's real crime , in the eyes of many , was committed on July 4 , 1910 , when he successfully defended his boxing title against Jim Jeffries , a white boxer who came to be called the `` Great White Hope '' because many white fans saw him as the best chance to wrest back a boxing title from the African-American champ . Johnson beat Jeffries , who had come out of retirement for the fight , before a stunned , almost entirely white crowd in Reno , Nevada . Race riots followed . More than 20 people were killed and hundreds were injured . Most victims were black . So when they `` could n't beat him in the ring , the white power establishment decided to beat him in the courts , '' Burns said in his documentary . Johnson fled to Europe in 1913 while free on appeal . But after years of fights overseas , including the eventual loss of his title in Havana , Cuba , in 1915 , Johnson came home . He turned himself over to U.S. authorities at the Mexican border in 1920 and served 10 months in prison . He died in a car wreck in 1946 . `` Back then , if you were black and you were told that you did something wrong , you really had no recourse , '' Linda Haywood , Johnson 's great-niece , recently told CNN . `` You just accepted what was done because black people were basically powerless and voiceless . Jack may have been a rich boxer , but he could n't fight the system . '' McCain and King introduced resolutions calling for a presidential pardon in 2005 and last year . McCain , who says he made a mistake by once voting against a federal holiday for the Rev. Martin Luther King Jr. , sees the pardon as a way to right an old wrong . `` The Jack Johnson case is an ignominious stain on our nation 's history , '' he said on the Senate floor in the spring . `` Rectifying this injustice is long overdue . -LSB- The resolution recognizes -RSB- the unjustness of what transpired , and sheds light on the achievements of an athlete who was forced into the shadows of bigotry and prejudice . ''