Members of the RCMP stand outside the La Loche Community School in La Loche, Sask. Monday, Jan. 25, 2016. (Jonathan Hayward / THE CANADIAN PRESS)

SASKATOON -- The Court of Appeal for Saskatchewan has dismissed an appeal from the La Loche shooter that he should not be sentenced as an adult.

Justice J.A. Tholl wrote in his decision that the sentencing judge had not erred her sentence.

"Applying the applicable standard of review, it is my opinion the sentencing judge did not commit an error in principle, fail to give appropriate weight to a relevant factor or rely on an irrelevant factor in reaching her decision that a youth sentence was insufficient ... As a result, this Court cannot interfere with that determination."

Chief Justice Robert G. Richards concurred with the ruling, while Madam Justice Georgina Jackson dissented.

La Loche Mayor Robert St.Pierre told CTV News he was happy and the court made the right decision.

The community has had to go through the court process for nearly four years and a youth sentence would have "added more to the community," he said.

Closing this chapter will allow the community to "move forward," he said.

In the appeal hearing held in April, defence lawyer Aaron Fox argued that the shooter, now 21, faced cognitive and mental issues that affected his maturity and level of blame.

The appeal court's decision is "disappointing," Fox told CTV News on Thursday.

He and the family will now consider whether to take the case to the Supreme Court of Canada.

"We will have to take a look at the decision. He and his family will have to make a decision."

The shooter was sentenced as an adult last year to life in prison with no chance of parole for 10 years after pleading guilty to first-degree murder, second-degree murder and attempted murder.

Four people were killed and seven were injured by the shooter at a home and at the high school in La Loche in January 2016.