By Keith Staskiewicz
Updated August 03, 2015 at 07:38 PM EDT
Credit: AP Photo/The Denver Post, Andy Cross, Pool, file

Jurors will consider the death penalty as one possible punishment for convicted Aurora, Colorado theater shooter James Holmes. The decision, announced Monday, came in the wake of a unanimous vote on the part of jurors in the trial’s sentencing phase, which began last week and included the testimony of three dozen witnesses, Holmes’ sister and parents among them. Although his family spoke about Holmes’ childhood and asked the jurors to spare their son’s life, the panel ultimately decided the aggravating factors of the shooting were sufficient to possibly warrant capital punishment, leaving the death penalty on the table.

On July 16, Holmes was convicted of 24 counts of murder in the first degree for the 2012 shooting spree that left 12 people dead and 70 wounded at a midnight screening of The Dark Knight Rises in the suburban Denver movie theater.

Holmes had pleaded not guilty by reason of insanity, with defense attorneys arguing that the 27-year-old neuroscience student had suffered a psychotic break and thus was not responsible for his actions in the massacre. Prosecutors meanwhile sought to counter that plea with a series of expert witnesses who testified that, while Holmes was mentally ill, he still retained the capacity to distinguish moral right from wrong.

After jurors turned in a verdict in which the word “guilty” was repeated 165 times in over an hour, Holmes’ lawyers have been seeking a life sentence for their client.

The trial will now move into its third phase as the jurors return to deliberations to determine whether to sentence Holmes to life without parole or death.

This latest development comes only two weeks after the third anniversary of the shooting.