The man charged with killing two people and wounding five others in a Halloween night stabbing rampage in Quebec City wanted to be an "agent of chaos" and had been planning an attack for six years, a jury heard Monday.

Carl Girouard's trial on two charges of first-degree murder and five of attempted murder opened with the judge informing the court the defence will argue Girouard should be found not criminally responsible. That means he admits to the stabbings but will plead that he was suffering from a mental disorder at the time of the events.

Prosecutor Francois Godin told jurors that Girouard, 26, travelled to Quebec City from his home in Ste-Therese, a suburb north of Montreal, on Oct. 31, 2020, because he wanted to "fulfil a malevolent desire … to make a statement."

"He wants to change other people's opinion of him," Godin added, saying that in Girouard's eyes, violence reflected superiority over others. "He wants to show his courage by doing things that others would not do, so he wants to kill people."

The attack claimed the lives of Suzanne Clermont, 61, and Francois Duchesne, 56, while five others were injured.

According to the Crown, Girouard left home in his car, taking a Japanese sword called a katana that had a 76.9-centimetre blade. He wore black jogging pants, black leather boots, a kimono and a black mask. After arriving in Quebec City, he drove around before finally parking in front of the Chateau Frontenac hotel in the city's historic quarter.

"At that moment, he gets out of his vehicle with the katana, and there he sets off on his murderous journey and sows terror in his path," Godin told jurors.

The prosecutor said the evidence will show that by the end of 2014, Girouard had "verbalized what he wanted to do, how he was going to do it and the things he had to accomplish before committing these actions."

For example, Girouard had said he needed to have a tattoo removed before taking action, and on the date of the killings he was no longer tattooed, the court heard. He also said he wanted to act before age 25, and at the moment of the crimes, he was 24.

The first witness to take the stand was Hugo Mercier-Villeneuve, an educational psychologist at an adult training centre that Girouard attended in 2014.

He told the court that during a meeting with the accused, Girouard spoke about needing to stand out from others and about an idea that had occurred to him. Girouard was evaluated because he had expressed suicidal and homicidal thoughts in some of his writings. He told Mercier-Villeneuve about a costume he kept locked at home -- a sword, a hoodie, shoes, pants and a mask -- to help carry out his plan.

"He is aware that these are fairly serious comments," Mercier-Villeneuve said. During cross-examination, he acknowledged that Girouard's comments could be seen to have been "ambivalent" and "incongruous."

Girouard was eventually referred to a social worker, Charles-Andre Bourdua, who met him nine times up to the end of the summer of 2015. Bourdua told the court that from the beginning, Girouard spoke of "killing people with a sword … randomly."

Jury selection was completed quickly Monday, with eight women and four men chosen to hear the case.

The trial is expected to last between four and five weeks and will focus on Girouard's mental condition at the time of the events, Quebec Superior Court Justice Richard Grenier told the jury.

"The most important admission in this case is that Mr. Girouard is the perpetrator of the homicides," he said. "You will have to assess the evidence that will be presented and determine his responsibility."

Defence lawyer Pierre Gagnon told the court a psychiatrist as well as the mother of the accused and a correctional officer will testify for Girouard.

-- This report by The Canadian Press was first published April 11, 2022.