WAGONER (AP) — Family members of a Broken Arrow teen who died two years ago are optimistic that a grand jury investigation will yield the answers they have sought.

The probe into the death of 18-year-old Jarret Clark starts today in Wagoner County District Court with jury selection.

Friends and family of the teen, who was found dead in Fort Gibson Lake in 2006, joined earlier this year to collect more than 8,500 signatures on a grand jury petition to start the process.

“We have all different types of emotions going through us right now,” said Tammy Slater, Clark’s mother. “But we’re very hopeful going into this that we’ll find the answers we need and bring some closure to this. We’ve been waiting a long time to see this happen.”

Clark died under mysterious circumstances in May 2006. He disappeared while attending a post-graduation party at the lake and was found dead four days later in the water following a massive search.

A state autopsy could not determine whether Clark, who had been drinking, accidentally drowned or was killed. But Slater and other family members have claimed steadfastly that Clark was involved in a fight with other youths and that foul play was involved in his death.

Neither the Wagoner County District Attorney’s Office nor a previous multicounty grand jury found sufficient evidence to file charges or indict, however.

Slater has not thought ahead to what the family will do next if the probe doesn’t bring the hoped-for results.

“I don’t really want to think about it. I just want to think positive,” Slater said.

Attorney Mark L. Collier, who represents the Slaters, said the family is down to its last shot.

“I don’t think there is a next,” Collier said. “Frankly, they’ve gone to every possible jurisdiction that could file this case. This is their sole remaining option.”

But Collier is confident they won’t need any more options.

“I think there is sufficient evidence and I believe we have as good a chance of getting an indictment in this case as with any of the ones I’ve been involved with,” he said.

Slater said she and her husband, Eric Slater, Clark’s stepfather, will testify first before the new grand jury, followed by other witnesses.

It’s been a year of emotional twists and turns: After the grand jury probe was approved in June, one of the key witnesses named in the probe petition, Brandon Hargrove, 20, of Wagoner, died in a car crash in July.