I think a PI should have been hired by at least four weeks after the abduction. Nobody needs hindsight to know the investigation was in trouble after a month and no arrest.
Remember also the lead detective said this early on; 'this is as close to a vanishing as I have seen.'
That statement told us how difficult the case was.
We must remember we don't really have an obvious crime scene, we don't have a time for the crime, there is no physical evidence, there are no witnesses and if it's a homicide there is no body.
Can anyone think of a more difficult case to work on?
Come to think of it what do you work on?
The CCTV pictures I guess. Of course these aren't exactly easy either.
Would you bet your house that the suspect is either male or female?
Then there is the annoying problem of the suspects face being obscured in one set of photos and looking like an ant at 30 yards in the other set.
This is one tough case.
In March 2006 we knew Jennifer had vanished and we had those two pictures of a POI.
In May 2007 we know Jennifer has vanished, we still have two pictures of the POI, and now we know the POI is the suspect and the suspect parked her car.
I doubt even Sherlock Holmes would want this case landing on his desk.