Police have not confirmed whether they believe the dramatic event at the Metropolis concert hall on Sept. 4 was an assassination attempt.
Richard Henry Bain, 62, faces charges including first-degree murder, three counts of attempted murder and 12 offences in connection with the shooting.
"The person could have had important psychological problems, I understand. But, he intervened against a sovereigntist by protesting that he feared for anglophones. I think there was a political aspect to this attack," said Marois during an interview on Tout le monde en parle that aired Sunday on CBC's French service, Radio-Canada.
Marois said she first believed Bain was trying to enter through the back door to kill people in the audience.
"At night, when I returned to my family, I told myself, 'It was something against me. I was the target,'" she said.
Bain is accused of killing lighting technician Denis Blanchette and seriously injuring Denis Courage, two other workers at the Metropolis.
After the shooting, Bain allegedly attempted to set the venue's back door on fire, the suspect, wearing a blue robe and with his face partially covered by a balaclava, was arrested outside the Metropolis and a rifle was seized. At that moment, the alleged shooter said, "the English are waking up."
Police confirmed that two guns had been confiscated after the incident.