Moments later - after being asked to drop the weapon - DePape abruptly struck Mr Pelosi before being wrestled to the ground by officers. The entire incident was caught on body cameras worn by the officers.

In addition to a fractured skull, Mr Pelosi suffered injuries to his arm and hand. He was struck three times during the attack.

In a letter filed ahead of the sentencing, Mrs Pelosi called on the court to hand down a "very long" sentence for DePape, adding that she and her husband have never been able to discuss the incident.

"Paul and I have not discussed the events of that horrible night," she wrote. "Paul doesn't want to undergo revisiting it, and the doctors' advice is that discussing the vicious assault would only renew his trauma."

During the trial, Mr Pelosi testified that DePape said his plan was to "take out" Mrs Pelosi, whom he referred to as the "leader of the pack".

"It was a tremendous shock, looking at him, looking at the hammer and the ties," Mr Pelosi recalled. "I recognised I was in serious danger. I tried to stay as calm as possible."

After the attack, Mr Pelosi said his next memory was waking up to a "pool of blood" and being rushed to the hospital.

In his own letter to the court before the sentencing, Mr Pelosi said he is still grapping with the effects of the attack.

"I walk slowly and have difficulty with my balance. Nearly every day I get headaches that become migraines unless quickly addressed," he wrote. "I need to sleep during the day and cannot tolerate bright lights or loud noises for extended periods of time."

DePape's court-appointed lawyer, Jodi Linker, argued that her client was motivated by right-wing conspiracy theories, which the defendant believed "with every ounce of his being".

Prosecutors, however, argued that DePape had a "plan of violence", noting that he told investigators he had a "target list" and plan to break Mrs Pelosi's kneecaps if she did not reveal "the truth". At the time of his arrest, DePape had zip ties and duct tape.

Outside the courthouse, DePape's son told reporters that his father's prison sentence was the same as the death penalty.

"I think that's a really long time, because if you think about it, he's already nearly 50," Sky Gonzalez said, according to the Associated Press. "Basically, it's just a death sentence."

In addition to the federal charges, DePape is facing separate state charges stemming from the attack. They include burglary, assault with a deadly weapon, elder abuse, and attempted murder.

He faces life imprisonment if convicted of those charges. He has pleaded not guilty.

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