My normal feeling to to focus on someone close to the victim... like the family, estranged ex husband, stalker boyfriend, crazy co worker, etc. Shelly Mook, Drew Peterson's two wives, Lacey Peterson, etc. fall into this category. This kind of killer usually goes to some great lengths to hide the body. But also they are at least suspected by the rest of the family and LE even if its hard to officially charge them. Missing women in this category all have friends of family that come forward and say so and so threatened them, was abusive, told them if they left they would kill them, etc.
Plus you have just the crazed killer stalker like the guys that killed Rebecca Schaeffer, John Hinkley, etc. They dont seem to hide their action or the body.
In Holly's case you can probably rule out a crime based on a risky behaviours like drug deals gone bad (Krista Dittmeyer)
You can also probably rule out some kind of mental disorder or drug/alcohol abuse (Mitrice Richards).
Then you have the sex offender type killer who may abduct someone from a home or out in the community. Again they seem more impulse type killers. They may hide the body but not so well and because they are repeat offenders they get caught. This would be someone like John Gardener who killed Chelsea King and Amber Duboise. He was already in the system for raping another girl and the case against him in Chelsea and Ambers deaths quickly built up against him. Chelsea's body was found fairly easily and evidence recovered from the crime scene led right back to Gardener.
Oh and don't forget the girls that hang out with suspect friends, often while drinking or doing drugs. I suspect this in cases like Lauren Spierer, Brittnee Drexel, etc. Someone that was with those girls when they disappeared knows what happens. And again, the families of those girls have said as much. They may not be able to name someone but they have ideas. And those families have spoken out. Morgan Harrington sort of falls into this category too. None of her friends seemed to pay much attention and its not known why she left the concert. And the last time she was seen was hitch hiking on a bridge... Its not like she was taken from her house she was out where someone could get her.
True stranger abductions seem somewhat rare compared to all those other kinds of abductions and murders. They do happen but I think all of the above scenarios happen 100 times more often. Elizabeth Smart isnt really a total stranger abduction either. Her family and sister knew the guy that took her they just didnt recall him.
In Holly's case none of the above SEEM to apply. Possibly someone had been to the home to do some work or something and saw Holly. But no one has ever recalled such a person or said "hey what about that guy that was here in February... "
When the case was first reported the details did make Clint look suspicious. Remember this was said to be a home invasion, that clint saw his sister being dragged away, etc. I think most people should wonder wtf didn't he try to stop it? That obviously influenced Pat Brown's statements that have aired on TV a couple times implicating Clint. No matter where or how the reporting errors were made, they were made, and that made an impression on people. Its like when the newspaper prints something wrong and everyone reads it, no one sees the correction 3 days later on page 200.
But so far this whole story just does not add up. He saw it he didnt see it she was in fear for her life, they were just walking, there was blood, the blood was a tiny amount, the blood was pools or flecks, the blood was across the yard, there were 2, 3, 4, 911 calls. The mom called 911, the mom didn't call 911. People went into the woods searching, they didnt go into the woods...
