Dramatic video showing the shooting inside the lobby of a conservative Christian lobbying group in D.C. was released by the group Thursday.
The video shows Floyd Corkins II shooting a staffer for the Family Research Council last August.
During the incident, Corkins fired several shots and wounded Leo Johnson, who is seen struggling with Corkins in the video.
Corkins pleaded guilty to three charges in February: interstate transportation of a firearm, assault with intent to kill while armed and committing an act of terrorism while armed.
Prosecutors say he should spend 45 years behind bars. Corkins was carrying almost 100 rounds of ammunition, more than a dozen Chick-fil-A sandwiches and told authorities he planned to kill as many people as possible.
The Associated Press contributed to this story.