Lawyers for the gunman who killed six worshippers in a Quebec City mosque announced Friday they are appealing the killer’s sentence of life in prison with no possibility of parole for 40 years.

Alexandre Bissonnette should instead be given a sentence of 25 years before being eligible for parole for his Jan. 29, 2017 attack on the Quebec City Islamic Cultural Centre, the motion filed with the Quebec Court of Appeal says.

Legal aid lawyers Charles-Olivier Gosselin and Jean-Claude Gingras argued the trial judge erred when he sentenced Bissonnette on Feb. 8. It was the harshest prison term ever in Quebec and one of the longest in Canada, which since a 2011 Criminal Code reform has allowed consecutive life sentences for multiple murders.

Quebec Superior Court Justice Francois Huot’s sentence was “illegal” and “manifestly unreasonable,” the defence lawyers wrote. The sentence, however, was well under the six consecutive life sentences – 150 years before being eligible for parole – sought by the Crown.

The six life sentences were automatic after Bissonnette pleaded guilty to first-degree murder, but the defence had asked that they be served concurrently.

Huot rejected the Crown’s call to sentence Bissonnette to 150 years with no chance of parole, arguing a sentence of 50 years or more would constitute cruel and unusual punishment under the Canadian Charter of Rights and Freedoms.

The judge instead rewrote the 2011 consecutive sentencing law, section 745.51 of the Criminal Code. Huot gave himself the discretion to deliver consecutive life sentences that are not in blocks of 25 years, as had previously been the case, arriving at a total of 40 years.

In their motion, Gosselin and Gingras claim the 40-year sentence was still cruel and unusual.

Quebec Attorney General Sonia LeBel and the Crown can also appeal the sentence. The deadline to do so is Monday.