As he enters his final days in office, President Obama has an opportunity to invoke his pardon authority to correct the unjust conviction of an immigrant of color during the 1920s, an era of fierce anti-immigrant, racist, and Ku Klux Klan power. The victim was Marcus Garvey, whose dynamic crusade to rescue people of African descent from Jim Crow and Africa from colonialism would lead to a sentence in federal prison in 1923 and eventually deportation to his native Jamaica.

Garvey arrived in New York in 1916, a dangerous moment for Africa and African Americans. The European powers were engaged in a blood bath over African and other colonial possessions, and the United States was preparing to enter World War I on the side of the Allied powers to "make the world safe for democracy."

Garvey set up headquarters in Harlem for his Universal Negro Improvement Association (UNIA) and African Communities League. Within a few years, his slogan, "Africa for the Africans: Those at home and those abroad," and his larger campaign to have his people study their history, take pride in their color, and regain their rights and power, spread across the country. It became the largest black mass movement in American history. By the early 1920s, the UNIA had established 700 branches in 38 states, in large cities and small towns, and claimed millions of members throughout the world. His "Negro World" newspaper sold 200,000 copies a week.

The Black Star Line was set up as a trading and shipping company to move goods and people among Africa, the Caribbean, and the Americas. This caught the attention of young J. Edgar Hoover, recently installed to lead what would become the Federal Bureau of Investigation. Hoover saw efforts for racial justice as subversive and feared a rising "Black Messiah" who could lead his radicalized people toward full citizenship.

A Hoover memo of the time describes Garvey as a West Indian who "has also been particularly active among the radical elements in New York City in agitating the Negro movement." Hoover added, "Unfortunately, however, he has not yet violated any federal law whereby he could be proceeded against on the grounds of being an undesirable alien, from the point of view of deportation."

Hoover hired four black agents to infiltrate the UNIA in the hopes of initiating a conviction and deportation proceeding "against [Garvey] for fraud in connection with his Black Star Line propaganda."

Arrested for mail fraud in connection with his shipping line, Garvey hoped to put his crusade on trial. He first fired his attorney for saying he should take a plea bargain. In a legal ordeal against the federal government that he little understood, Garvey chose to represent himself. The judge said he was unfit, scoffed at his defense, refused at times to let him question witnesses, sustained prosecution objections, and declared his own objections.

Garvey faced witnesses coached by the prosecution. A leading witness admitted that a crucial document he said Garvey had given him actually was handed to him by a federal prosecutor. Then the witness broke down and could not even prove he really worked for Garvey's company. Another government witness presented an empty envelope missing the "evidence" he claimed had been inside.

Garvey was convicted and sentenced to five years. Immediately, nine of the 12 jurors filed a petition asking he be pardoned.

In 1927, Attorney General John G. Sargent found Garvey's case so discriminatory and oppressive that he convinced President Calvin Coolidge to commute his sentence to time served. Coolidge agreed and Garvey was deported to Jamaica. With his brilliant wife, Amy Jacques, he moved to London. In 1940 he died in poverty as a war against fascist imperialism raged in Europe.

Marcus Garvey, who profoundly influenced African independence leaders from Kwame Nkrumah in Ghana to Nelson Mandela in South Africa, and even more fighters for justice and freedom around the world. deserves a pardon. Malcolm X used to tell audiences: "All the freedom movements that are taking place right here in America today were initiated by the work and teachings of Marcus Garvey." In 1965, the Rev. Dr. Martin Luther King Jr., speaking of Jamaica's first national hero, said "You gave Marcus Garvey to the United States of America and he gave to the millions of Negroes in the United States a sense of personhood, a sense of manhood, and a sense of somebodiness." To King, Garvey was "the first man of color in the history of the United States to lead and develop a mass movement. He was the first man, on a mass scale and level, to give millions of Negroes a sense of dignity and destiny and make the Negro feel that he was somebody."

Today, the campaign for a full pardon is led by the freedom fighter's son, Julius Garvey, a New York-based cardiothoracic vascular surgeon. He has generated support by prominent people and organizations across the United States and around the world, including the Congressional Black Caucus, 18 members of Congress, Jamaica Prime Minister Andrew Holness, and Ndaba Mandela, grandson of Nelson Mandela.

This simple justice is long overdue in a country that has saluted its freedom fighters through the ages. Grant a posthumous pardon to Marcus Garvey.

William Loren Katz is author of "Black Indians: A Hidden Heritage" and 40 other books on African American history.