Lincoln's dressmaker Elizabeth Keckley overheard Mrs. Lincoln yell to Parker, "So you are on guard tonight, on guard in the White House after helping to murder the President." Parker attempted to defend himself stating that he "could never stoop to murder much less to the murder of so good and great a man as the President. I did wrong, I admit, and have bitterly repented." Mrs. Lincoln told Parker that she would always think he was responsible for the President's death and angrily dismissed him from the room. Parker remained on the police force until 1868 when he was fired for sleeping on duty. He later went back to work as a carpenter. He died of pneumonia complicated by asthma and exhaustion in Washington, D.C., on June 28, 1890. He was buried in an unmarked grave at Glenwood Cemetery. His widow, Mary America Maus, was buried next to him upon her death in 1904 as were their three children. There are no known images of him.