Acting on a tip from an employee in the Atherton public library, police from Atherton and Redwood City on Oct. 30 arrested Thomas Willis Hemmenway, a Redwood City resident and registered sex offender, and booked him into San Mateo County jail, police said.
An investigation by the Atherton police had begun the day before the arrest after a library employee called to report seeing a man using a public-access computer in the library to view what appeared to be child pornography, Lt. Joe Wade of the Atherton Police Department said.
Mr. Hemmenway, 52, was arrested on charges "related to the control and possession of child pornography," Lt. Wade said.
Mr. Hemmenway is also on parole from state prison and suspected by his parole officer of violating the conditions of his parole, reason enough to put him in jail, Lt. Wade said.
The employee left the library around the same time as the man in question and provided police with a description of his car and license plate number, Lt. Wade said.
Police crosschecked the information with a government database, found the vehicle's registered owner, and learned that he is forbidden to possess pornography, Lt. Wade said. The library computer, which was seized, contained incriminating evidence of pornography, he said.
After a conversation with Mr. Hemmenway's parole officer, police from Redwood City and Atherton arrested him at his residence, Lt. Wade said, adding that a search warrant is being drawn up to search his home.