Zoogster -
People involving the system upset with the result?
Happens all the time in domestic situations. Spouse/parent calls police because they want the police to give them some additional authority in thier family issues, and then the police or the law does not end up working out as the person intended. They then complain about how the system deals with thier family issues.
In many places the local authorities encourage this relationship because it gives them authority above and beyond what would otherwise be viable or legal. A parent for example working with probation gives the law what is essentialy an inside witness against criminal individuals. They make the parent or spouse believe they have the best interest of the individual in mind, but in reality thier prime concern is holding the individual accountable for anything possible. So they encourage pressing charges in any and all situations, and are going to try to gain a foothold in any household they can.
I have known familes with children who have had similar problems to eachother, and usualy the one that got the law involved earlier turned out worse.
I know one who had a son that was a little bit of a pothead, missed school on occasion and had parents that tried to work with him, eventualy he got a decent job and moved out and has been successful last I heard.
Another with a kid who had a violent temper and would punch holes in a wall or door on occasion, who was very successful in school and a star athlete who had parents work with him and he eventualy went on to college and has done well.
Another family with the same type of kid called the police and was encouraged to get him on probation to give the parents additional leverage in situations. This got him a record, and caused him to go from a kid with an occasional problem, that did well otherwise and had good people in thier life, to one making friends in juvenile detention facilities and surrounded by gang members and other criminals within the system. Now they have grown to be a real problem and there is not much hope for them anymore.
So in general involving the system in family affairs is a stupid solution. If you need police in a marriage for example to keep the peace, then what you really need is to move on in life.
With children it is more of a judgement call because you cannot just move on. However in all cases once the law is involved the quality of life for all involved will go downhill.
If you think making someone under your roof a felon, or even just having them get probation for a misdemeanor is not going to effect your privacy and lower your quality of life then you are wrong. Someone in a household with such a person has almost the same level of scrutiny and infringement as the person actualy in trouble.
The system however encourages it because it gives more freedom to law enforcement in general. Any household with even a single individual on some sort of probation/parole etc no longer requires a warrant or the same level of legal restraint to deal with. So the more households the better in the eyes of the law.
Just like everything it is also a career and a "business" in that it employs more and more people who promote its use. Just as lawyers promote the use of lawsuits, many peace officers (police, probation, parole, corrections, etc) promote the use of the correctional system.
Police are for dangerous situations, this particular case seems to qualify. Once one calls in the system however thier say in matters no longer counts. She involved police with her daughter, what happens after that point is not in her control. The system is not an entity that cares for the people involved, it is a big machine and oils its own wheels. Invite it into your home at your own peril. I say anyone that would require you to invite it into your home should no longer be in your home.
I am reminded of a recent case not long ago of some hmong kid that fired a shot into the ceiling when the parents said he could not use the car. They called the police who snuck in and shot him dead as he was armed and dangerous. That event was memorable because of the amount of shots fired to put him down, it was a lot. The parents in that case were all upset that the police did not deal with thier precious kid the way they wanted when they called the police on a 'man with a gun', who has shown a willingness to use it. The police care mainly about going home that night, and are not going to take the precautions a love one might feel could be taken first. That amount of risk is not acceptable to them.
Most cops i've met have been pretty damn good people. And even those will say ya there is that (insert explicative here) every now and again... 
