Death Penalty for Clifford Boggess

Along time ago, Clifford Bogess was convicted of murdering two elderly people because he needed money to get back to college and fix the motor on his car.
later on, Bogess held captive in a maximum security prison in Texas.  Because of his crime, he was found guilty by the court and sentenced to death.  Eventually, he died from the death penalty.
Historically, Texas has the most death penalties for criminals than any other state in America.
When watching the film, the debate was simple, should Bogess be sentenced to death or not?
In my opinion, he should be sentenced to death.  He should be dead because when watching the film, his backstory was that he was adopted and had the mind of a killer.  He had no remorse for the two people that he murderded.
Because of the murder of the loved ones of family,  it crushed the members in to bits of pieces.  And so death was the only way that brought justice to them.  Death may not bring back their loved ones but it would bring closure to the members of the family and make other families and not suffer from the same pain they have gone through.
The Mitigating Factors that prevents him from the sentence of death is that he believes that he was a changed man and a Christian.  He also believed that God will forgive him, He is his lawyer, and that his artwork is his last work.  The Aggravating Factors of Bogess' case was that he was mentally insane and made up his mind of kiling the people with no remorse.
When being held captive, he believed that he was a changed man.  You can try and change especially Boggess himself but the convictions of people and Bogess himself will folow them for the rest of their lives. 
Also Boggess can look at his life as an artist or a Christian  for societal value but he will remain a killer.  There's no change at al whatsoever.