The death of a Washington police officer who died by suicide just days after he was assaulted during the Jan. 6 attack on the U.S. Capitol has been ruled a line-of-duty death, a finding that makes his widow eligible for enhanced survivor benefits.

Metropolitan Police Officer Jeffrey Smith died on Jan. 15.

“Based on evidence submitted by the petitioner and the Department, we find that Officer Smith sustained a personal injury on January 6, 2021, while performing his duties and that his injury was the sole and direct cause of his death,” the D.C. Police and Firefighters’ Retirement and Relief Board wrote in a letter obtained by NBC News on Wednesday.

Smith, according to his widow, described Jan. 6, 2021, as the worst day of his life. Erin Smith later said her late husband was "just not his normal self" after Jan. 6.

A former D.C. chief medical examiner said in an earlier review that there was “a direct cause and effect relationship between the line of duty work trauma on Jan. 6 and Jeffrey Smith’s death,” adding that Smith had “no prior history of depression, mental health issues or mental health treatment.”

Body camera video shows at least two assaults on Smith on Jan. 6: one inside the Capitol and another outside the building, when he was struck with a flying metal pole. The video confirmed what Erin Smith recalled her husband as having told her: that he'd been “punched in the face, hit in the head with a metal pole.”