I think all our DNA should be available to police for elimination purposes. Over the course of this thread I hope I can convince you all that it is the best course of action.
Why is a drug offense a different matter?
You make it sound like being 'on file' is a punishment in itself. If everyone was on file, the second a murder is committed the police will have a good chance of knowing who was around before and after - giving an immediate list of suspects and witnesses.
Let me put this into perspective:
A young model was raped and murdered a couple of years ago. Her assailant was only caught because, after arrest for a minor offence was his DNA taken and matched.
If he had been on file, he would have been arrested within days.
This would be especially useful in rape cases I would imagine.
http://news.bbc.co.uk/1/hi/england/london/4281686.stm
In this case, the three men arrested were all innocent.
It took over two years for the killer to be brought to jusctice.