NORTHAMPTON — A Florence man who last week pleaded guilty to 13 counts of possessing child pornography was sentenced Wednesday to serve four years in jail followed by five years probation.

Hampshire Superior Court Judge James Manitsas also ordered Philip Brocklesby, 61, to register as a sex offender, to have no unsupervised contact with children, to stay at least 100 feet away from schools, playgrounds and parks and to permit probation officers to search his electronic devices. He was given credit for one day spent in jail.

Arguing for an eight-to-10-year prison sentence, Assistant District Attorney Anne Yereniuk told the judge that the case had presented the commonwealth’s investigator with the largest collection of images and videos depicting child sexual abuse he had ever observed. At a conservative estimate, she said, Brocklesby possessed 100,000 files, mostly of prepubescent boys.

“The only way such activity comes to law enforcement’s attention is if the offender slips up,” Yereniuk said.

She said Brocklesby frequented the dark web, where computer users’ identifying information is hidden, but he uploaded one file on Facebook that led the social media company to file a report with the National Center for Missing and Exploited Children, which passed the information on to Massachusetts State Police. Police traced the IP address to Brocklesby’s home, executed a search warrant at his Bridge Road home and arrested him in September 2020.

Yereniuk acknowledged that some child porn offenders receive no more than probation but, she argued, “This is not one of those cases.” While Brocklesby was not charged with dissemination or distribution of child pornography, she argued there was evidence that he tracked victims in cases from other parts of the country.

For children whose sexual abuse is documented in online imagery and their families, it’s a lifelong sentence, she said, citing testimony from people whose lives have been upended in this way. Buttressing her argument, Yereniuk had a lawyer for one child sexual abuse victim to call in to the court and read the victim’s mother’s statement on how the trauma had affected her child’s life and hers.

Defense attorney James Goodhines began by praising the work of Yereniuk and the lead investigator, Northampton Police Detective Sgt. Corey Robinson, in putting together the prosecution’s case. But, arguing for a suspended jail sentence of two years, with three years probation, he termed the commonwealth’s sentencing request as “unbelievably excessive,” and its presentation “filled with material that is so irrelevant.”

The commonwealth, he said, was looking to punish his client, who has no criminal history, for the conduct of others. He said Brocklesby, a Chicopee native, had spent three years in the Coast Guard and became a bus driver when he returned to western Massachusetts in 1987. He bought a house in Florence in 1996, but always had trouble maintaining relationships. Only recently had he learned that he had an autism spectrum disorder, and Goodhines argued that there was a direct connection between Brocklesby’s condition and his possession of child pornography. Yereniuk had previously dismissed any link between the two.

There was no evidence that his client had disseminated images depicting child sexual abuse and he had not been charged with doing so, Goodhines said, and the commonwealth should not be trying to punish him for doing so.

“It’s misconduct, it’s offensive,” he said, his voice rising.

Manitsas offered no comment in passing sentence, though he declined the defense counsel’s request that Brocklesby, who used a cane in court, be allowed a day’s grace to retrieve special clothing items from his home that he needs for his edema.

Staff Writer James Pentland can be reached at jpentland@gazettenet.com.