Decker was a criminal and bounty head.
Decker came into possession of high grade explosives and distributed them with a trucker ship that had an Asian goddess on it. For this, he had a 12 million Woolong bounty. Eventually, he decided to go eat at Woody's, however, unbeknownst to him, several bounty hunters had heard about his presence in the area. Faye Valentine went to Woody's to wait for him and, when she mistakenly captures someone else, he overhears that he's in danger and leaves. She saw him and pursued, but Decker easily threw an explosive behind him, crippling her ship, the Red Tail.
Decker escaped to his ship and headed for the asteroid belt. During, he hit Otto's ship but didn't stop. This attracted attention later on, when, near the Linus Mine, he saw another trucker ship, VT's. He saw that VT was after him and headed for the mine to escape. She pursued him even after he ejected another explosive her way. It missed, but caused a chain reaction in the mine's systems and a cave-in on his truck, killing him.