The Pennsylvania police officer who received a tip about Luigi Mangione being spotted at a local McDonald's has said he and his supervisor were so sceptical that it was the suspected shooter they exchanged jokes about it.
Joseph Detwiler told a Manhattan courtroom on Tuesday that tip ultimately led to Mangione's arrest for the shooting of UnitedHealthcare CEO Brian Wilson in New York last December.
Mr Mangione, 27, who has pleaded not guilty to state and federal murder charges, was in court for a second day of proceedings to decide if evidence from his arrest is admissible in trial.
His defence team wants key evidence thrown out, arguing that he was not immediately informed of his rights.
"He said, 'if you get the New York City shooter, I'll buy you a hoagie from a local restaurant,'" Mr Detwiler said in court of text messages exchanged with his lieutenant. "I said: 'Consider it done.'"
The tip Mr Detwiler was responding to was played in court on Monday. It had been called in to a 911 dispatcher by the McDonald's restaurant manager in Altoona, who said that customers believed they had spotted the suspect.
Police body camera footage and accompanying audio was also played in court during pretrial hearing, which could last several days, as defence attorneys are expected to call a host of witnesses.
Mr Mangione was arrested days after he allegedly shot Mr Thompson, a father of two, as he was walking into an investors' conference on a busy Manhattan street on 4 December 2024.
The shooting sparked an interstate manhunt for the suspected killer and sparked debate over the for-profit health insurance industry in the US.
Mr Detwiler, an Altoona, Pennsylvania, police officer, and his partner were sent to the fast food restaurant to follow up on the tip.
Although the police officer doubted its veracity - telling prosecutors that he responded to the dispatch call in a "semi-sarcastic" tone - he learned within an hour that it was legitimate.
Mr Detwiler said that he saw a man wearing a large coat, brown beanie and medical mask sitting at a table next to the bathrooms, just as the tipster had said. He said he walked by, wanting to see what Mr Mangione would do when he saw the uniformed officers, and asked for his name and ID, which turned out to be fake.
He said he then asked the man to pull down his mask and knew almost immediately it was Mr Mangione.
The footage played in court shows Mr Mangione eating hash browns and a steak sandwich, as Christmas music plays in the background, CBS News, the BBC US partner, reported.
Mr Detwiler, who could be heard whistling along to the music, said in court he was "trying to keep things calm and normal".
The officer told Mr Mangione that they were confirming his ID when they were actually waiting for backup, making up a story about the restaurant having a policy about loitering. Mr Mangione had been at that McDonald's for about 40 minutes.
Mr Mangione's defence team is hoping to convince a judge to exclude evidence including a 9mm gun and a notebook in which prosecutors say he set out a motive.
Mr Mangione's legal team is also pushing to bar the federal government from seeking the death penalty.
His attorney Karen Agnifilo pressed Mr Detwiler on how he identified Mr Mangione.
Ms Agnifilo said the dispatch call was "low-priority" and Mr Detwiler agreed that "it didn't sound serious on the radio", nor did they use lights and sirens when they approached the McDonald's.