A Boise man who owned more than 30,000 files of child pornography and sexually abused his wife’s daughter — as well as used her in his own child pornography — was sentenced to life in prison Tuesday morning.

In July, a jury convicted Justin Anderson, 29, of 28 criminal counts, including sexual abuse, sexual exploitation and lewd conduct with a child. Prosecutors said police found between 30,000 and 35,000 files of child pornography on multiple electronic devices Anderson owned — and, as Kassandra Slaven, one of the prosecutors said Tuesday, officers were never able to fully break the encryption on his computer.

Anderson had married a homeless woman with a 5-year-old daughter as well, said 4th District Court Judge Deborah Bail, although the marriage appeared to be a ploy for Anderson to gain access to the girl, whom he abused and photographed in the creation of his own child pornography.

“He acted on it very quickly — so quickly that I think it’s a reasonable assumption that the reason he became involved with the victim’s mother was to gain access to the victim,” Bail said.

Anderson was charged in February. Police began to investigate him after they found he was using methamphetamine, Bail said Tuesday. That investigation led to his arrest, and later his jury trial. A jury convicted him of all 28 counts he faced — although, Slaven reminded Bail, those 28 counts were simply representative of the full scope of Anderson’s crimes.

“I doubt the court or the defense would like me to file 30,000 counts of child pornography,” Slaven said.

In asking for a fixed life sentence for Anderson, Slaven argued victims of child pornography face a life sentence themselves, knowing the images and videos of them will live forever on the internet. Plus, she said, although Anderson did not create all the tens of thousands of files he owned, his downloading of them perpetuated their creation and the harming of children he had never met. And, Slaven said, Anderson was also abusive both to the girl and her mother as well.

“He knew (the victim’s mother) had been sexually abused as a child and he wanted her to talk about that because it was arousing to him,” she said.

He showed pornography to her daughter as a grooming tactic, Slaven said, before he abused her himself.

“He basically did everything to her he could think of,” Slaven said.

Even in jail, she said, deputies found hand-drawn images of child pornography in his belongings.

All of that concerned Bail too, who spoke at length about the harm child pornography does to children, and her concern for others in the community if Anderson were to be released.

“Any adult who looks at the actual (child pornography found on Anderson’s phone)...can see in the eyes of the children their extreme sadness,” Bail said.

Anderson, she said, helped further an “ugly market for the torment of children.”

Anderson for his part declined to speak during the sentencing. Brian Marx, his attorney, said Anderson had moved around a great deal as a child himself, and said his mother left the family early on. He asked Bail to sentence Anderson to a set five years in prison, with another 15 possible after that, giving the Idaho Commission of Pardons and Parole room to evaluate him at that later date.

Instead, she handed down the heaviest sentence possible — life in prison.

“It’s not a sentence I’ve commonly imposed, and I think it’s something to be careful of, but I think he presents such an extraordinary risk to little children that (this sentence) is necessary both as a penalty and to protect the most vulnerable members of our society,” Bail said.

Tommy Simmons is the Ada County public safety reporter for the Idaho Press. Follow him on Twitter @tsimmonsipt