Lawyers for James Holmes -- accused in a shooting rampage that killed 12 at a "Batman" movie in Colorado -- have offered to enter a guilty plea and have their client spend the rest of his life in prison in exchange for avoiding the death penalty.
Prosecutors have not yet accepted the plea deal. They were expected to announce April 1 whether they would seek the death penalty.
Rob McCallum, a spokesman for Colorado courts, confirmed the public defender's filing of the plea deal on Wednesday.
At his arraignment on March 12, defense attorneys declined to enter a plea for Holmes.
Instead, a judge entered a plea of not guilty, opening the door for attorneys to mount an insanity defense.
Earlier, Circuit Court Judge William Sylvester ruled that Holmes would have to waive medical confidentiality, turn over medical reports, and agree to be drugged for a psychiatric exam if he wanted to plead not guilty by reason of insanity.
Defense lawyers claimed in court documents that Holmes was hospitalized for several days after the shooting and required restraints.
Holmes, 25, is accused of 166 felony counts of murder, attempted murder and other felonies in the July 20 shootings at the crowded midnight screening of “The Dark Knight Rises” in Aurora, Colo. In addition to the 12 people killed, 70 others were wounded.
Prosecutors say that Holmes planned the attack for months, time in which he cased the theater complex and compiled a small arsenal of weapons. The former graduate student put on a police-style helmet and body armor, tossed a gas canister into the theater crowd and started shooting, prosecutors said.
His defense lawyers had hinted at an insanity defense, NBC station KUSA reported, but had given no definitive indication of how they would plead in the case.
If Holmes does change his plea, his attorneys would need to ask the judge for a hearing.
A trial date was set for Aug. 12.