If they don't find the body, and there are no witnesses, and there is either little or no circumstantial lab evidence linking him to her disappearance, and he keeps his mouth shut, and his lawyer runs the usual legal arguments on the cops and prosecuters, Scotty boy is about ready to set sail on the 'Love Boat."
Prediction: Scotty and his "new" squeeze will be leaving the state in six months to a year for some balmy clime! Laci's parents will realize (if they have't already) that Scotty pulled a fast one on them and played them all for suckers. His parents, however, will continue to insist that their little boy had NOTHING to do with Laci's death.
Just a guess, but I will predict a 5'4" blond bombshell named "Candy". We'll see!