Ronald Haskell Jr. is accused of killing Stephen and Katie Stay along with four of their five children inside their home in 2014. Only daughter Cassidy Stay, then 15, survived a bullet wound to the head.
The trial began in late August, and from the closing arguments, it was clear the details of the case are heart-wrenching.
READ MORE: 5 years after murders, man accused of killing Spring family execution-style goes to trial
Haskell pleaded not guilty by reason of insanity. Prosecutors argued in closing statements that Haskell killed the family as retribution for helping his ex-wife, Melanie, separate from him. Katie Stay was Melanie's sister.
WATCH: Full closing arguments in Stay family massacre trial
A forensic psychologist testified the day before for the prosecution, saying Haskell is not insane. Legal experts say the insanity defense is rarely used and hard to prove.
"You may stop and say to yourself, 'Well, anyone that kills that many people must be insane,' but that's not necessarily true," said legal analyst Steve Shellist. "You can have someone that kills people that knows what they're doing is wrong, so they may have some other mental health issues. So they can still be found guilty, because they're not insane as the law defines 'insane.'"
In day three of the trial, prosecutors took jurors behind the scenes of the standoff following the murders. There was testimony from officers who were at the scene, and from the negotiator who spoke with Haskell on the phone after he dialed 911 to speak with them.
READ MORE: Murder defendant told investigators, "I'm just not right in the head"
Jurors deliberated for just a handful of hours before being dismissed around 6 p.m. They will resume Thursday morning.
Haskell faces the death penalty if convicted.
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