In February 2012, Mr. Romano pleaded guilty and was sentenced to 15 years in prison. And that is when his unraveling began, according to his lawyers. In jail, Mr. Romano quickly gained 100 pounds. He became fixated on his fraud case and how he was serving more time than some people who had committed violent crimes. He fantasized about ways to hurt the judge: with a cement-mixing truck, by putting him in a hole or with a shark. (The lawyers clarified at trial that this was not prison lingo — Mr. Romano meant the fish.)

In the jail law library in July 2012, Mr. Romano met a fellow inmate who had also dealt with Judge Bianco. That set Mr. Romano off. The inmate, who became a government informant in exchange for a potentially reduced sentence, later testified that for almost three hours, Mr. Romano talked about “how he was screwed” and about killing the judge.

Image A surveillance photo of Mr. Romano, in jail for fraud, meeting with an undercover police detective who posed as a hit man. Credit... United States Attorney's Office

The inmate offered to put Mr. Romano in touch with a man who could kill the judge for him. In August 2012, Mr. Romano gave the would-be killer a starter assignment for $3,000: to beat up the mechanic who was holding on to Mr. Romano’s cars because of nonpayment. Bigger jobs could follow, Mr. Romano said.

And they did, quickly. After the hit man — actually a police detective — returned with a staged photo of the beat-up mechanic, Mr. Romano’s friend Mr. Mirkovic relayed instructions in a Home Depot parking lot.

“Judge Bianco, accident; Lara Gatz, disappear,” Mr. Mirkovic said as he checked the spelling of the name of the prosecutor, Lara Treinis Gatz, on his smartphone so that there would not be any confusion. (The exchange was secretly recorded by the hit man.) Mr. Romano wanted Ms. Gatz’s body concealed in a 35-gallon drum, he wanted her severed breasts returned to him, and he would pay a bonus for both of their heads in formaldehyde.

The hit man agreed to the price of $40,000. Told the plan was in place by Mr. Mirkovic, Mr. Romano said on a phone call that he was “dancing around and singing and stuff, you know?”