Portola Valley resident Stephen Wolf, 65, pleaded no contest Tuesday to charges of possession of child pornography, according to the San Mateo County District's Attorney's Office.

At a hearing set for May 30, he could be sentenced to as much as one year in jail, prosecutors said. The no-contest plea included a condition that he not be sent to prison. Prosecutors had been seeking a sentencing option of up to 16 months in state prison, but the judge rejected it, District Attorney Steve Wagstaffe said.

It's standard practice for San Mateo County prosecutors to ask for a prison option for "people who are fascinated by child pornography," and common practice for judges to reject that option when the defendant has no history of actual sex offenses, as was the case this time, Mr. Wagstaffe said.

Nevertheless, Mr. Wolf will have to register as a sex offender, Mr. Wagstaffe said. And the Department of Justice may add his name to a list associated with Megan's Law, which makes public "certain information on the whereabouts of sex offenders so that members of our local communities may protect themselves and their children," according to a summary of the law by the California Department of Justice.

"The law is not intended to punish the registrant and specifically prohibits using the information to harass or commit any crime against a registrant," the summary says.

Mr. Wolf is out of custody on $10,000 bail.

Mr. Wolf and Menlo Park resident Charles Vela Reyes Jr. were two of nine men arrested on March 22, 2012, during a county-wide sweep of 11 homes by detectives from a regional Internet-crimes task force. Both men had pleaded not guilty. Mr. Reyes' trial is set to begin on May 6.

In the arrests, detectives seized computers containing pornographic images "and other evidence linking the men to the distribution and/or possession of child pornography," the Sheriff's Office said. Mr. Wolf's computer contained images of nude girls ages 6 through 12 who were "engaged in sexual activity," prosecutors said.

More than 100 investigators from more than 20 law enforcement agencies participated in the sweep, including the Sheriff's Office, the Menlo Park Police Department, the FBI, the U.S. Postal Inspection Service, and a "homeland security" investigative arm of U.S. Immigration and Customs Enforcement (ICE).

Mr. Wolf entered his no-contest plea on Tuesday, March 19, in a pre-trial conference with Superior Court Criminal Presiding Judge Jonathan Karesh.

Mr. Wolf's attorney, Jonathan D. McDougall, has not yet responded to an interview request.

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