He is portrayed by James Pizzinato.
During the Korean War, Petty joined the Marines, and became a combat engineer in the 15th unit. Despite his efforts during the war, Petty was never awarded a Silver Star medal. Petty, realizing that children were being used to place bombs in the field, planted landmines in the playgrounds and water sources of the village Wonju. As a result of his actions, Petty was court martialed and served five years in a military prison. During his imprisonment, he repeatedly requested for a Silver Star medal, but was denied repeatedly.
Upon his release, Paxton went on to plant bombs in multiple parts of San Francisco. This resulted in heavy civilian casualties, though the fourth bomb wasn't discovered. Following this, Paxton was apprehended and incarcerated in Alcatraz.
Paxton was tortured at Alcatraz in order to reveal the whereabouts of the fourth, undetonated bomb. Lucille Sengrupta, the Alcatraz psychiatrist, attempted to extract information out of him without his knowledge. While being lightly electrocuted, Paxton began singing a Korean lullaby that was recorded on tape. Tommy Madsen, another innate, revealed that every line of the song revealed a different location of the bomb.
The information on the fourth bomb was given to SFPD officer, Emerson Hauser, who located it to Mount Sutro. The landimes were detonated without any casualties. Following this, Paxton and the other inmates vanished and were presumed dead.
Paxton resurfaced in 2012 in San Francisco, setting off four land mines in Pine Street Park. He was immediately identified by the Alcatraz Task Force, but managed to escape. In retribution for being denied Silver Star medals, Paxton had been using them as tools for more chaos. At a Presidio graveyard, Paxton murdered a security guard and panted more mines in the area. Paxton demanded a ransom of $651 000 dollars for the location of the bombs.