Michael D. Cohen says he has been left disbarred, financially crushed and personally embarrassed and humiliated after being sentenced to three years in prison for federal crimes. He says he regrets that he thought “being Donald Trump’s lawyer made him a ‘big man.’”

Mr. Cohen, the disgraced former lawyer and fixer for President Trump, made the comments in a letter to a federal judge on Wednesday in which he portrayed himself as a broken man and asked the court to allow him to serve the remainder of his sentence in home confinement.

Mr. Cohen, 53, began serving his sentence in May and is in a minimum-security camp at the Federal Correctional Institution in Otisville, N.Y., about 75 miles northwest of New York City.

Mr. Cohen wrote that he now realizes, as he walks the Otisville Camp paths, that he “in fact ‘sold his soul,’ and foolishly frittered away his integrity.”