West Roxbury sex offender convicted for possession of child porn

A convicted sex offender was sentenced to ten years in federal prison on a child-pornography charge last week, after admitting ownership of the files an FBI agent found on his computer via a file-sharing network.

William F. Murphy, a resident of Boston's only trailer park, initially told investigators he was only doing research to determine whether his girlfriend, with whom he was living, had been forced as a child to engage in sexual acts by a child-porn ring he wanted to expose, according to an affidavit by an FBI agent who investigated his case. He claimed he had tried to present the evidence to Boston Police, but that they had turned him away because of his status as a sex offender - he was convicted in 1988 of raping his 9-year-old stepdaughter.

An FBI agent says she was led to Murphy in 2008 when she did a search on LimeWire for keywords related to child pornography and found files on a computer that turned out to belong to Murphy's girlfriend - who told investigators the only people who actually used the machine were Murphy and her ten-year-old daughter.

Murphy was charged with one count of knowingly accessing child pornography with intent to view.

The case evolved as a part of Project Safe Childhood, a nationwide project to battle the serious, increasing wave of child sexual exploitation and abuse. Launched by the Department of Justice in 2006, and led by the U.S. Attorney's Office, CEOS, Project Safe Childhood Marshals and other state, federal and local initiatives, the project aims to capture and prosecute those who use the internet to exploit children.

• FBI affidavit