[6] Since joining the staff of The Dallas Morning News in 1984, Leeson has covered local and regional news and issues, such as homelessness and natural disasters; national stories on death row inmates across the United States; international conflicts in El Salvador, Nicaragua, Panama, Peru, Sudan, Angola, Kuwait and Iraq in the first and second Gulf Wars; earthquakes in Turkey; and apartheid in South Africa.

[5] His 1985 series on homelessness earned him a Robert F. Kennedy Journalism Award, an honor he received again in 1994 for his coverage of the civil war in Angola.

[4][7] While photographing protesters during the buildup to the ousting of Manuel Noriega in 1988, Leeson was wounded when a shotgun pellet entered his cheek, chipping his tooth and sending him to a Panama City emergency room.

[10] In 2008, Leeson decided to accept a buy-out offer and leave The Dallas Morning News, as part of an A. H. Belo Corporation cost-cutting measure involving buyouts of more than 400 journalists.

[12] Subsequently, numerous incidents have occurred in which soldiers, photographers, or others have passed off Leeson's work as their own, either on photography sites, blogs, or print periodicals.