Grand Jury Investigation.

Former Colorado attorney general Ken Salazar launched a grand jury report to investigate what authorities knew about Eric Harris and Dylan Klebold prior to the shooting. A search warrant was drafted for the Harris home, but was never submitted to a judge.

The grand jury discovered plenty of 'missing' documents. The grand jury also reported that authorities held a secret meeting a few days after the attack and decided to hide the existence of the search warrant from the public.