Class-z said:
As an innocent parent, you cooperate to the fullest, make yourself available to LE and you become "TRNASPARENT" so they can rule you out and get past you. The Ramsey's NEVER did this.
And what do you do when it is made quite clear that the only interest the police have in you is in collecting evidence to charge you? That they will follow no other lead, they are positive you did it, and any little difference in memory, anything they can get and warp to be a confession, they will use?
I keep thinking of the case in San Diego, where the police decided within minutes that the girls brother killed her - similar kind of bit - she was killed in her bedroom, no one but family there. They spent years trying to convict this kid, to the exclusion of all else - in particular to the exclusion of even looking at a transient they had picked up in the same neighborhood, trying to get into people's houses, looking for a girl he was mad at. The police even confiscated and held onto this transient's clothes to use as proof he didn't do it, if he ever came up as an alternate suspect - but they never tested or looked at the clothes. When they were forced to, many years later, after a judge had (like the Ramsey's) ruled against them - they found the little girl's blood on his sweatshirt! Believe it or not, some of them still to this day think it was the brother and his friends.
They weren't weird kids, no reason, the police just didn't think any intruder could have come and gone without leaving a trace, and after some serious sleep deprivation, pressure, and lies applied to the brother, he cracked a little ("If what you say is true, that you've got my DNA on the knife that killed my sister, I must have done it - but I don't remember it!") which they called a confession.
The police are usually good, and generally, I'd cooperate with them fully. But I wouldn't necessarily trust them with a kid, and interrogations of grieving parents - you've got to be pretty strong minded to be able to deal with your grief at what you just found out happened to your little girl, your natural guilt that as a parent you should have been able to protect them, and to deal with sleep deprivation, and every mind game police experts can throw at you.