Michael Benoit told The Associated Press in a telephone interview from his home in Alberta, Canada, that his family is shocked and in disbelief.
"His comment to me on Father's Day: 'Where am I today?' He said, 'Unfortunately I'm on my way to work, dad. I would like to have spent the day with my family.' That really wouldn't give you an indication of someone who would do what he did a week later," the father said.
Michael Benoit said his family has been overwhelmed by the media attention the case has drawn.
"We have no understanding of why it happened," he said of the killings. "We need some time to gather our thoughts and wait and see. There's still more information that's going to come out from toxicology tests that will give us some understanding of why this happened."
Benoit said the test results, which could take several weeks to be completed, "could give us closure."