Ian Mercer was at a loss Saturday for how to explain the shooting at Umpqua Community College, in which his son, Christopher Harper-Mercer, is accused of killing nine people and wounding seven others.
Original reports said the 26-year-old had 13 guns; law enforcement later said they had found 14 firearms.
Speaking to CNN outside his California home, Mercer offered his condolences to the families of the victims, acknowledging that "I know words will not bring your family back." He expressed frustration at the now-familiar routine of some people calling for more gun control and lawsmakers accomplishing nothing.
"I'm not trying to say that [it's] to blame for what happened, but if Chris had not been able to get ahold of 13 guns, it would not have happened," Mercer said.
"Look all over the world. You don't see these mass shootings all over the world like you do in the United States," said the British-born Mercer. "Someone has to ask themselves, 'How is it so easy to get all these guns?'"
The New York Times looked at 14 recent mass shootings, including Thursday's tragedy in Roseburg, Oregon, and found that more than half of the gunmen, including Harper-Mercer, had purchased firearms legally despite their criminal histories and/or documented mental health problems. Harper-Mercer had 14 firearms bought legally either by himself or family members.
Ian Mercer said he had not seen his son since "before he left for Oregon" two years ago. Chris Harper-Mercer lived with his mother in Oregon. Former neighbors in California told The New York Times that the mother and son would go to the shooting range together.
Mercer told CNN that he had no idea his son had any guns. He noted that he personally had never held a firearm in his life and summed up his philosophy as: "You don't buy guns, you don't buy guns, you don't buy guns."
Following his son's suspected suicide, Mercer now finds himself among the chorus of those calling for a change to the gun laws in the U.S.
"Even people that believe in the right to bear arms, what right do you have to take people's lives?" Mercer said. "That's what guns are: the killers. It's as simple as that. It's black and white. What do you want a gun for?"
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