A Manhattan attorney threw out all the books and paperwork in his office near City Hall — and then jumped to his death from a 12th-floor window, according to cops and sources in the building.

Leonard Morton, 45 — who recently separated from his wife — landed facedown on the scaffolding on Broadway near Barclay Street at about 7:20 a.m., law-enforcement sources said.

“For the past week something was definitely wrong with him,” said Juan Diaz, a receptionist at the law firm where Morton worked. “Usually he comes in and says hello and asks me how I’m doing. But for the past week he never said anything.”

A worker at the building said Morton — who lived on the Upper West Side — has had an office there for several years but only recently relocated to the 12th floor.

Morton, whose two-lawyer practice focuses on civil matters, formerly served as an administrative law judge for the city and was also a captain in the New York Army National Guard Judge Advocate General Corps.

His firm’s Web site lists clients like MSG, Lincoln Center for the Performing Arts, The Blue Note, and the Juilliard School of Music.

On his LinkedIn page, Morton spoke of his love of the musicians he represented.

“I am routinely and constantly humbled to be friends with and to be able to work, quite literally, with some of the best, kindest and most talented musical minds/talents in the world,” Morton wrote.

“My goal is to make sure that the world knows who they are and what their music sounds like.”

Morton went to undergraduate at the University of Michigan and studied law at Fordham University, according to his LinkedIn page.

Neighbors at Morton’s Upper West Side building said he had been depressed over the death of both parents and because of marital troubles with his wife.

“He lost his mom and dad within a very short period,” said a neighbor. “I know that was very hard on him. He was very upset.”

Morton’s separation from his wife also added to his troubles, said Upper West Side neighbor Laura Kenyon.

A video from his 2010 wedding shows him dancing with his pretty bride and posing for photos with his friends to the tune of “Here Comes the Sun.”

Additional reporting by Elizabeth Hagen and Josh Saul