A 49-year-old father of four who was unmasked by new DNA techniques tearfully apologized Wednesday for committing rape during a home invasion in 1991.

Thomas Craig Brodie, whose crimes were revealed only after Canadian authorities resorted to a method known as investigative genetic genealogy, told a sentencing hearing in provincial court in Calgary that he is no longer the man that he was 30 years ago.

“I ask your forgiveness for the terrible things I did,” Mr. Brodie said, addressing a victim who was watching proceedings via videolink.

Provincial Court Judge A.A. Fradsham reserved his decision on how long Mr. Brodie will spend in prison. Prosecutors are pushing for a penitentiary sentence of up to seven years, though the defence is urging a shorter term.

The court was presented with contrasting pictures drawn of a man 30 years apart. The defence emphasized how Mr. Brodie, who was supported by his wife and children, is a loving family man. But the prosecution said he must be condemned for what he did in 1991, when he was an intoxicated 18-year-old who donned a disguise, broke into a house and repeatedly raped a 28-year-old woman.

“I would give almost anything to be able to take back that night,” Mr. Brodie told the court. He said he had always struggled with how he had hidden his dark past. “Many times over the years, as I got older, I thought about going to police and confessing to them what I had done. But I was scared.”

The Globe and Mail reported last month that…