CALAIS, Maine — A 48-year-old Calais man who works in the radiology department at Calais Regional Hospital was summoned last week and charged with failure to register as a sex offender.

Nearly 20 years ago, Russell Staples, then 29, of Hartland entered a guilty plea in Somerset County Superior Court to unlawful sexual contact. The case apparently involved a minor who had not yet reached age 14.

Staples was sentenced in 1990 to three years with the Department of Corrections with all but 30 days in jail suspended and three years probation. The incident happened in 1989.

Details of the crime were not available Monday evening, and Evert Fowle, district attorney for Somerset and Kennebec counties, did not return a telephone call.

Sgt. Chris Donahue of the Calais Police Department said Monday that Staples was summoned on March 19 for failure to comply with the sex offender registration law. He is scheduled to appear in Calais District Court on May 5.

“He came in [to the police department], picked up the summons and left,” Donahue said.

The sergeant said he learned of Staples’ status when he received an e-mail from officials at the Maine Sex Offender Registry saying they were looking for Staples. Donahue said it appeared that Staples’ name came up while officials were reviewing past convictions of sex offenders who had not registered.

“My understanding is he had not filled out his initial papers and had not registered at all,” Donahue said.

Donahue said Staples had lived in Calais before, but did not know for how long nor did he know when Staples had returned to Calais.

Calais is not the only agency arresting or summoning sex offenders who fail to register.

In February, the Washington County Sheriff’s Department and Maine State Police made a sweep of the county during a 14-hour period that, among other arrests, netted three convicted sex offenders who had failed to meet registration requirements.

Washington County Sheriff Donnie Smith said at the time that there were about 100 convicted sex offenders living in Washington County. Most are in compliance with the registry law and regularly update their addresses as required, either with the community where they live or with the Sheriff’s Department. A small number, however, fail to register or give out false information as to where they live, he said.

Michael St. Louis, chief deputy of the Washington County Sheriff’s Department, said Monday that schools often call his agency to find out whether someone they want to hire is on the sex offender registry. “That is why it became a mission [of the department] because some of these people are not registered,” he added.

Not all sex offenders are prohibited from having contact with children, St. Louis said. “Some of them the only sentence they have is to do their time, of course, and then register — it doesn’t mean they can’t teach or go to a basketball game,” he said. He said it was up to the judge to make no contact with children part of the sentence.

But deciding who should register under the Sex Offender Registration and Notification Act of 1999 remains up for debate. In February two men who were convicted of minor sex offenses several years ago and sentenced accordingly for their crimes challenged the constitutionality of the registry in the Maine Supreme Judicial Court, claiming it was an unfair punitive action. No decision has been made in that case.

The Legislature is looking at LD 568, a bill that would make four distinct changes to Maine’s sex offender registry laws including requiring only those persons convicted on or after June 30, 1992, to register.