McClain, who played football at Decatur High School and then Alabama, was arrested Thursday and charged with four misdemeanors after allegedly firing a gun next to the victim's head.
Details of the alleged incident were contained in a news release issued by Decatur Police. The Decatur Daily photographed the linebacker smiling widely while handcuffed and being placed in a police car.
McClain was also charged with menacing, reckless endangerment and discharging a firearm in the city limits.
According to police, the alleged victim had been at a residence on Skyview Street in southwest Decatur when he was involved in a fight with another man that caused injuries to his head and face. Police said he was bleeding from the nose and mouth as he spoke to responding officers.
The alleged victim told police he crawled to his car after the fight and was approached by McClain, who aimed a pistol at him. While he was still on the ground, McClain walked over to him and put the gun to his head.
"The victim reported that he begged McClain not to shoot him and that McClain took the gun away from his head, held it next to his ear and fired it," the news release says.
Officers responded to reports of "shots" being fired but believe only one was discharged.
They could not initially arrest McClain or the man who fought the alleged victim because the offenses did not occur in their presence. But after police filed a report, investigators met with the alleged victim and assisted him in obtaining warrants for McClain and Jarodiuas Willingham, who was charged with third-degree assault.
The Raiders were apparently aware of McClain's arrest, although he has not been ruled out of Sunday's game at Miami.
McClain was the No. 8 overall draft pick in 2010 and has made 142 tackles with 2 1/2 sacks and one interception in 25 games for the Raiders, all starts. He won the 2009 Butkus Award as the country's top linebacker and helped the Crimson Tide win the BCS National Championship.