Assemblyman Nathan Fletcher has begun to explore tightening state sex offender laws in the aftermath of the rape and murder of Poway teenager Chelsea King.

The San Diego Republican said he plans a deliberative approach, working with state and local authorities to determine where the system may have failed the 17-year-old out for an afternoon jog last Thursday afternoon.

"Our laws are supposed to protect the innocent, but they didn't protect Chelsea King," Fletcher said.

The suspect in the case is John Gardner III, a registered sex offender who was arrested Sunday. He pleaded not guilty this afternoon in his first court appearance.

Authorities are still working to positively identify a body found buried near Lake Hodges as that of Chelsea.

Fletcher said he wants to gather more information and allow time for the family and community to mourn before pressing legislation.

"This is a time for grieving and comforting the family," he said.

Then, he continued, "it will be a time for a real conversation about how to make policy to protect our children. We have to look at every option."

Among those:

• Expand Jessica's Law to limit how close registered sex offenders can get to places frequented by children, such as parks and schools. Current law only prohibits them from living within 2,000 feet of a school or park. Authorities can impose specific restrictions, however, on a case-by-case basis. Such limits have been proposed before, but the measures stalled in the Legislature.

• Fletcher also is considering whether existing monitoring technology could be used to trigger a warning for authorities when a parolee comes too close to parks and schools. Registered sex offenders are tracked using global positioning systems since the passage of Jessica's Law in 2006.

• Lengthier prison systems, perhaps even mandatory terms, also must be weighed, he said.

"We are trying to identify the gaps in the system," Fletcher said.

Sen. George Runner, R-Lancaster, and the author of the landmark Jessica's Law, said, "We're reviewing what took place to see where there might be some loopholes."

Crime Victims United, a statewide advocacy group, said it is also researching the case to determine whether steps can be taken to avoid future tragedies.

"At this point it's hard to know entirely what the appropriate fix is," said Dawn Koepke, legislative advocate on behalf of Crime Victims United.

Gardner, a 30-year-old from Lake Elsinore, served five years of a six-year sentence for lewd behavior and false imprisonment stemming from an incident involving a 13-year-old girl in 2000.

At the time, the San Diego District Attorney's Office decided not to seek the maximum penalty of nearly 11 years.

State correctional authorities emphasize that Gardner was not under their supervision at the time of Chelsea's disappearance. He has spent three years on parole until September 2008.