(NBC NEWS) -- Nearly eight months after the deadly theater shooting in Aurora, Colorado the man accused in the massacre is expected to enter a plea Tuesday during his arraignment.
James Holmes is accused of opening fire during a midnight showing of "The Dark Knight Rises," killing 12 people and injuring dozens of others.
It's widely speculated, in part because of recent court filings, that Holmes may enter a plea of Not Guilty by Reason of Insanity.
Under Colorado law, he would then be examined by state psychiatric experts and his past mental health records made available as evidence.
Holmes' attorneys filed motions earlier this month claiming Colorado's insanity laws are unfair to defendants because they require disclosure of potentially incriminating information.
They also claimed the laws are too vague, especially in how they relate to death penalty cases.
On Friday, District Judge William Sylvester rejected those arguments, refusing to declare the laws unconstitutional.
"It's a huge case socially, and it's a huge case legally likely to create precedent good or bad that will govern future prosecutions," notes legal analyst Scott Robinson.
Holmes faces 166 felony counts including first degree murder and attempted murder.
Prosecutors have not said whether they intend to seek the death penalty.
After the plea they have about 60 days to announce their decision.