wow okay thanks, and how about if people are on the dna database, do you think they will do the worse crime possible if they know they are going to get caught either way?
Though the proverb says, "you might as well be hung for a sheep as a lamb," deriving from the 18th century laws where the death penalty was mandatory for thefts of value above a shilling (equivalent to much less than £10 in today's values), that's not about getting caught but about the seriousness of the penalty...
On the contrary, they *don't* know they wil be caught. They may not even consider it. (Though some of the most sickening crimes in recent years have been exacerbated by ill-conceived attempts to eliminate DNA evidence by burning the victim with chemicals or fire.) You are falling into the fallacy that criminals do crimes *in order* to be wicked. They don't. They do them out of perfectly ordinary motivations: greed, gluttony, lust, pride, anger, envy, laziness and
fear - which in their particular cases and circumstances outweigh the law and, more importantly, the social conditioning to obey it and to treat their fellows well. They may do further and perhaps worse crimes to avoid getting caught, but that too is a balance of inhibition and motivation.
You are also, like many people, misunderstanding the consequence of being on the DNA database. It does not mean 'you will be caught'. DNA evidence can often do no more than place someone at the scene of the crime. Say your school is burnt down by a fire started in a classroom. The place may have a full collection of pupils' and teachers' DNA. But is that evidence that any particular one of them - or any of them at all - was involved in the arson?