Yesterday, Texas jurors watched Eddie Ray Routh’s chilling confession video in day four of the “American Sniper” trial.

In the video, Routh admits that he knew his actions were wrong and apologizes for killing Chris Kyle and Chad Littlefield, saying, "I guess I need to be doing more thinking in this town than hurting people. I'm sorry for what I've done and if I could have done it differently, I would have done it so much differently."

The defense claims Routh was psychotic at the time, but could his confession hurt his case?

Judge Andrew Napolitano explained on "Fox and Friends" that in the state of Texas it's the defendant's obligation to come forward with evidence that he is insane or was insane at the time of the crime. Judge Nap noted that in most other states, the burden is on the government to prove that the defendant is sane.

Judge Nap said that the video could actually help the defense demonstrate that Routh was not behaving normally.

"On the other hand, the evidence of his guilt is overwhelming. Texas is a state that rarely, rarely excludes murder convictions because of insanity, because of the attitudes of Texas laws and Texans," Judge Nap said.

Watch Judge Nap's insight in the clip above.