If convicted on federal charges, Christensen, 60, faces up to 30 years in prison and a $250,000 fine on each of two charges. In the federal system prisoners are not eligible for parole until they complete 85 percent of their sentence.

"We're distressed they're going to these lengths," said Christensen's lawyer, Jeffrey Pine, of Providence. "This is overkill."

US Attorney Robert Clark Corrente announced the charges against Christensen last Friday at a press conference launching Project Safe Childhood, a Department of Justice program targeting exploitation of children over the Internet.

Corrente's spokesman, Tom Connell, declined to respond to Pine's accusation.

"Any action we take in the case will take place in court," Connell said. "We will not engage in repartee in the newspaper."

Last week, in US District Court in Providence, Christensen was arraigned on one charge each of interstate travel to entice a minor in sexual conduct and using interstate commerce to entice a minor, according to Corrente's office. The retired software engineer, who is married with two grown sons, pleaded not guilty and was released on a $10,000 bond. He is confined to his home with an electronic monitoring bracelet, and is not allowed access to computers or the Internet. He also is prohibited from any contact with minors.

A woman who answered the phone at Christensen's Granuaile Road home declined to comment.

Federal prosecutors took over the case from Rhode Island's attorney general, who had charged Christensen with one count of indecent solicitation of a minor.

"Our mutual goal is to use the best possible laws to prosecute cases. In this case the federal laws pack more punch than the state laws," said Mike Healey, spokesman for the Rhode Island attorney general.

In December, Christensen received five years probation after pleading guilty in Plymouth Superior Court to soliciting sex on the Internet from a person he believed to be a 13-year-old girl. As in the Rhode Island case, the person was in fact a police officer.