A man charged with pushing his wife to her death from a cliff as they celebrated their wedding anniversary in Colorado's Rocky Mountain National Park tried to kill her once before, a prosecutor said in closing arguments Friday in the man's federal murder trial.

Assistant U.S. Attorney Suneeta Hazra told jurors that Harold Henthorn dropped a 20-foot beam on Toni Henthorn while they were working on their mountain cabin more than a year before her 2012 death. The beam fractured Toni Henthorn's vertebrae, and her husband's account of what happened didn't make sense, Hazra said.

Harold Henthorn, 59, is charged with first-degree murder in the death of his second wife, a wealthy Mississippi native who fell about 130 feet in a remote area where the couple was hiking on Sept. 29, 2012, their 12th wedding anniversary.

Prosecutors argued Harold Henthorn stood to benefit from $4.7 million in life insurance policies that his wife didn't know existed.

Henthorn's attorney, Craig L. Truman, has said the death was a tragic accident, and his client raced down the steep rocks to help his wife.

Harold Henthorn told investigators his wife fell over a ledge as she paused to take a photo. A coroner testified he couldn't determine whether the woman fell or was pushed.

Prosecutors argued the fatal fall was reminiscent of the death of Henthorn's first wife, Sandra Lynn Henthorn, who was crushed when a car slipped off a jack while they were changing a flat tire in 1995 — several months after their 12th wedding anniversary. Henthorn has not been charged in that case, but police reopened the investigation after Toni Henthorn's death.

On Friday, Hazra told jurors that Harold Henthorn scouted a remote area nine times before taking his wife there to kill her. She said he was seeking the "perfect place to murder someone," where there would be no witnesses and no chance of her surviving.

Toni Henthorn, 50, wasn't an avid hiker, so it didn't make sense that she would have gone willingly into such dangerous terrain, investigators testified during the trial. Park rangers said Harold Henthorn could not explain why he had a park map with an "X'' drawn at the spot where his wife fell.

Toni Henthorn was a successful ophthalmologist who also earned money from her family's thriving oil business.

Harold Henthorn told her he was a wealthy entrepreneur and persuaded her to move with him to the Denver suburb of Highlands Ranch. They had a daughter, now 9.

Prosecutors said Harold Henthorn made phony business cards to make it seem like he was a hardworking fundraiser for churches and nonprofits, but investigators found no evidence that he had any income from regular employment.