Ada County jurors for the first time Monday heard accused killer Robert Hall talk about what happened the night his wife’s boss and lover, lawyer Emmett Corrigan, was killed outside a Meridian Walgreens.

In an interview recorded at a hospital that night, Hall, his speech slow and slurred, told police that his gun fell out of his pocket and that he and Corrigan fought over it.

Responding to repeated questions from Meridian police detectives, Hall said he didn’t know how Corrigan was shot.

“What were you doing at Walgreens, Rob? Do you remember? Did you go there to meet somebody or did you go there to buy something?” a detective asked Hall.

Barely coherent, Hall said his daughter told him that his wife was at the store. Another man was there — “her boss” — and a fight ensued, Hall said.

Hall said Corrigan told him that Hall “mistreated his wife,” meaning Kandi Hall, with whom Corrigan was having an affair.

Hall is charged with first-degree murder.

The recording began a day of testimony by defense witnesses after a short opening statement by Hall’s lawyer, Robert Chastain. Chastain said prosecutors have not proved that Hall, 42 at the time, planned to kill Corrigan, 30, when the confrontation ensued at the store.

Jurors spent most of Monday hearing experts hired by the defense discuss bullet trajectories, gunshot residue and other forensic evidence. They claim it supports the theory that the gun fell from Hall’s pocket and discharged during a confrontation.

Police have said that a bullet that struck Hall’s head came from a self-inflicted shot, but defense experts said it likely was caused by one of the two bullets that struck Corrigan.

Robert H. Friedman, a physician at Idaho Physical Medicine & Rehabilitation and a program director at Elks Rehab, said Hall experienced “a moderate concussion” that led to some memory loss.

Pablo Stewart, a psychiatrist who works at the University of San Francisco School of Medicine, told jurors that at the time of the shooting, Corrigan was experiencing symptoms from steroid use that included impulsiveness and irritability.

In cross-examination, prosecutor Jason Spillman emphasized that Stewart never met Corrigan and that many other factors were contributing to a high stress level in Corrigan’s life.

Meghann M. Cuniff: 377-6418