The man who stabbed to death a 70-year-old woman who was walking her dog in Richmond has been found not guilty by reason of insanity, prosecutors said.

Richmond Circuit Judge Bradley B. Cavedo found Johnny Hughes, 53, not guilty Wednesday and returned him to Central State Hospital just outside Petersburg, where Hughes has been held since a few days after the Oct. 27 stabbing.

Hughes was due in court Wednesday so doctors could give a report on his mental condition. Deputy Commonwealth's Attorney Learned D. Barry said the two psychiatrists who evaluated Hughes determined he is insane.

Doctors will decide when he should be released, but Barry said Hughes' chances of ever getting out of Central State are slim.

Supervising Assistant Commonwealth's Attorney Elizabeth A. Hobbs said the commonwealth's attorney's office hopes Central State "keeps him as long as necessary to keep the community safe."

Hughes told police he repeatedly stabbed Susanne Thompson because he wanted money. She was out for a morning walk with her dog, Angie, near her home at Heartfields Assisted Living at 501 N. Allen Ave., when Hughes attacked her on West Broad Street near the Department of Motor Vehicles.

But after he killed her, Hughes left without taking anything, police say he told them.

During the investigation it was revealed that in the four months before the attack, mental-health workers visited Hughes 11 times to try to keep him on his medications.

Wilson Washington, chief executive of the Richmond Behavioral Health Authority, said yesterday that Hughes had received services at the authority's downtown offices.

"We're confident that he was receiving the proper treatment," Washington said. "From what I understand with Mr. Hughes, he had a long history of mental illness. We do have a process that we follow with those clients that are seriously mentally ill, and we try to monitor them very closely and makesure they get their medications. But a lot of those clients are just noncompliant. Sometimes they do decompensate and these kinds of things happen."

Washington, who took over as CEO last week, said the authority planned to put more focus on patients with histories of mental illness, looking at how they respond to treatments and medication.

Court records showed Hughes had been arrested twice in May 2007 at his Selden Street home in the city's East End for possession of a concealed weapon, a handgun.

Officials said evaluations performed on Hughes at the time of the gun arrests showed he did not need to be committed to Central State.

When Hughes was tried on those charges in Richmond General District Court in June 2007, a judge sentenced him to seven months in jail, with six months suspended, and ordered him to get treatment from the Richmond Behavioral Health Authority and to take his medications.

It wasn't until 17 days after the judgment that the health authority became aware of the judge's order. They started a monitoring program of Hughes, whose last contact with the agency was Oct. 16, 2007, less than two weeks before he killed Thompson.

In March, a Richmond General District Court judge ruled that Hughes was competent to stand trial for Thompsons killing.

Contact Jeremy Slayton at (804) 649-6861 or jslayton@timesdispatch.com.

Staff writer Wes Hester contributed to this report.