CENTENNIAL — Defense attorneys in the Aurora theater shooting case are challenging the reliability and relevance of electronic records extracted from James Holmes’ iPhone, computers, tablets and other devices, including a Bing.com search on the words “rational insanity.”

Holmes, facing first-degree murder charges related to the July 20, 2012, shooting that killed 12 and injured 70 during a midnight showing of a Batman movie, has pleaded not guilty by reason of insanity.

Prosecutors are seeking the death penalty in the case.

Defense lawyers want records excluded unless prosecutors can prove they were captured in a way that prevented modification or deletions — and only if they are relevant to the case, useful to jurors and more instructive than prejudicial.

Prosecution witness Aurora Det. Michael Leiker, who is certified in examination of digital evidence, testified in a pretrial hearing Thursday in Arapahoe County District Court that he retrieved and copied the equivalent of thousands of pages of electronic records.

The records included e-mails, voice mails, photos, videos, text messages and web browsing histories, including word searches on weapons, ammunition, movie theaters and the term “rational insanity.”

Under courtroom questioning, he described police methods for handling digital records retrieving digital files with various software prorgrams.

Holmes’ trial, which Judge Carlos Samour has estimated could last up to eight months, is now set to begin with jury selection in mid-February.

Aurora Det. Gordon Madonna, also a certified computer forensice examiner, testified Thursday afternoon that he retrieved the computers and other devices, such as an iPod Touch, a laptop, two personal computers and thumb drives, from Holmes’ Paris Street apartment after the shooting and later worked alongside Leiker to ensure they both used proper practices to obtain the content of several digital devices linked to Holmes.

Madonna said he and Leiker reviewed each others’ work. All the work was done at the Aurora police crime lab.

Defense attorney Tamara Brady asked Leiker if he looked at all of the seized digital content.

“No, I don’t look at everything” Leiker answered. “I cannot. I look at file types.

The detectives looked for records that were responsive to questions from investigators in the case.