QUEBEC -- Prosecutors have demonized Quebec City mosque shooter Alexandre Bissonnette and want to put him away for 150 years for political reasons, the killer's father said Thursday at the conclusion of his son's sentencing hearing.

"Alexandre is not a monster," Raymond Bissonnette told reporters outside the courtroom.

Rather, Alexandre is a mentally ill victim of relentless bullying and intimidation during his school years -- factors that could have played a role in the shooting, his father said.

"All our efforts to end the bullying failed," he said, flanked by his wife, Manon Marchand.

"In the closing arguments, the Crown said that all young people are bullied sometime in their lives and don't commit serious crimes," he continued. "I think this opinion does not do justice to the serious damage and suffering caused by bullying and intimidation."

Bissonnette, 28, pleaded guilty earlier this year to six charges of first-degree murder and six of attempted murder after he walked into a mosque in the provincial capital in January 2017 and opened fire.

The defence has argued Bissonnette should be eligible for parole after 25 years in prison, while the Crown wants Bissonnette to receive a 150-year sentence.

His father said the Crown ignored the fact his son was mentally ill by not ordering psychiatric examination after his arrest.

"Instead, the Crown decided to completely demonize him by any means in order to obtain a 150-year sentence, the greatest sentence ever given in Canada," Raymond said.

"One hundred years is actually a death sentence in disguise, we all know, all hope is extinguished. I fear in my son's case, actually, the Crown is seeking a political, not a judicial sentence."

Raymond also spoke about Quebec City's Muslim community, whom he said had "legitimate frustrations" regarding religious discrimination.

"I realize how much this community members feel isolated and misunderstood," he said. "I also realize that nothing will change their opinion about my son Alexandre, and I fully understand."

Quebec Superior Court Justice Francois Huot is expected to render his decision on Bissonnette's sentence Oct. 29.