Published: Oct 10, 2013 3:47 PM EDT

CENTENNIAL, Colo. (AP) - An investigator says an Internet search on the words "rational insanity" had been done on a computer belonging to Colorado theater shooting defendant James Holmes.
    
Detective Michael Leiker testified in a pre-trial hearing Thursday. He said he found evidence of the search on a computer he examined during the investigation of the July 2012 shooting at a suburban Denver theater.
    
Leiker says the search was done on the Bing search engine, but he offered no other details.
    
It wasn't clear who did the search or when it was done. Neither prosecutors nor defense lawyers asked him to elaborate.
    
Holmes has pleaded not guilty by reason of insanity to multiple counts of murder and attempted murder. He's accused of killing 12 people and injuring 70.
    
Prosecutors are seeking the death penalty.

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