John Rydberg, a chronic sex offender seeking release from state confinement after 18 years, was described by a psychologist Friday as a consummate sexual sadist who has manipulated and deceived his therapists for years.

Rydberg "has worked the system historically to maximize his self-interest,'' said Dr. Harry Hoberman. "He still represents a significant danger to the public.''

Hoberman testified Friday during the second of three hearings on Rydberg's future. Rydberg, 69, would become the first person ever released from the Minnesota Sex Offender Program, and his case has become something of a test for a new direction at the controversial program. An expert panel at the state Department of Human Services recommended supervised release for Rydberg, who has completed all treatment available at St. Peter, but department executives oppose the recommendation, and it must be reviewed by a special three-judge panel.

Hoberman spent much of the morning reviewing clinical documents chronicling the grisly and demeaning nature of assaults by Rydberg, whose record includes more than 90 sex offenses.

Hoberman also questioned Rydberg's credibility, arguing that he spoke evasively with therapists and minimized the harm he inflicted on people until he faced a polygraph test in November 2010.

"Up until then, he hadn't considered them victims,'' Hoberman said. "But when he thinks it's going to benefit him, he wants to do treatment.''

After a break for lunch, Rydberg's attorney, Brian Southwell, questioned the psychologist's conclusions. He challenged Hoberman's credentials to second-guess state treatment experts, noting that Hoberman has personally treated only one sex offender in his career.

Southwell also got Hoberman to concede that Rydberg has done everything asked of him during the six years he has lived in a low-security facility at St. Peter.

Rydberg was civilly committed as a psychopathic personality in 1993 after serving a lengthy prison term in Stillwater in connection with the rape of a Blue Earth County woman in 1979. He currently resides in a non-secure house on the treatment center campus in St. Peter.

The hearing is expected to resume June 10. Presiding is a special three-judge panel consisting of Ramsey County Chief Judge Kathleen Guerin, retired Dakota County Judge Leslie Metzen and Ramsey County Judge Joanne Smith.

Paul McEnroe • 612-673-1745