* Prosecution wraps up pretrial case with pictures
* Defense team declines to present evidence, witnesses
* Decision on whether case will proceed expected on Friday (Adds final evidence presented, hearing adjournment)
By Keith Coffman
CENTENNIAL, Colo., Jan 9 (Reuters) - Prosecutors wrapped up their pretrial case on Wednesday against the man charged with killing 12 people in last summer's Colorado movie theater massacre by showing photos he took of himself before the shooting, posed with guns and body armor.
The pictures, seized by police from the iPhone of accused gunman James Holmes, capped three days of hearings in which prosecutors laid out their case for putting Holmes on trial.
Defense lawyers declined at the last minute to present evidence or call witnesses of their own.
Holmes' lawyers, seen by legal experts as preparing for an insanity defense, had indicated in court filings before the proceedings that they intended to call two witnesses to testify about their client's state of mind around the time of the shootings.
After the prosecution rested, public defender Daniel King told the judge that his team "had a change of position."
"This is a preliminary hearing and not the proper venue or time to put on a show or truncated defense," King said.
The defense also declined to make a closing statement before the hearing was adjourned.
Arapahoe County District Judge William Sylvester said he was taking evidence presented this week under advisement and scheduled a new court hearing for Friday that he said would serve as a "status hearing and/or arraignment."
If the judge orders the case to proceed to trial, Holmes, 25, is widely expected to enter a plea of not guilty by reason of insanity.
The former University of Colorado neuroscience doctoral student is charged with multiple counts of first-degree murder and attempted murder stemming from the July 20 rampage at a midnight screening of the Batman film "The Dark Knight Rises" in the Denver suburb of Aurora.
In addition to the 12 people killed, 58 others were wounded in one of the deadliest mass shootings in U.S. history.
Authorities have offered no motive for the slayings. Holmes' lawyers have said he suffers from mental illness but they have not been more specific.
Wrapping up the prosecution's case on Wednesday, police detective Matthew Fyles ran through pictures that he said were taken by Holmes roughly six hours before the deadly assault on the Century 16 multiplex near his home.
In one picture, Holmes grinned while holding the muzzle of a handgun near his face. He stuck his tongue out in another photo.
His brightly dyed red hair was visible in both pictures, and he wore black contact lenses that made his pupils appear abnormally large. In another picture taken the same evening, his bed was strewn with guns, ammunition magazines, body armor and other gear.
In a self-portrait taken on July 5 Holmes posed with a semi-automatic rifle and wore the tactical body armor he was wearing when he was arrested. (Reporting by Keith Coffman and Laura Beth Coffman; Writing by Steve Gorman; Editing by Cynthia Johnston)