One of the most recent arguments being used against taking DNA samples is that currently black men are four times more likely to be on the database than white men. Firstly this is an argument against the current way of collecting data rather than an argument against the database itself. Secondly, this statistic is slightly misleading anyway - we are not comparing like for like, let me explain.
Those on the database are much more likely to come from the 15-34 age group where black people make up a much bigger percentage of this population. So the comparison needs to be between black and white males in this age group to make sense. As black/mixed race people make up almost 10% of this age group compared to less than 4% of the total population, this is likely to reduce the discrepancy considerably. Next we have to look at social class, if we compare working class white males with working class black males in this age group, the discrepancy would almost certainly disappear. It is clear the bias is just reflecting a wider social class discrimination (indirect racial discrimination) within society not direct racial discrimination.
Anyway, this argument, as I have already said is an aside, to be really fair we need to DNA database everybody - there need not be any stigma attached to being on this database. I would gratefully add my details if everybody in society had to be on it - as the benefits to me (and society in general) would outweigh my inconvenience. More dangerous criminals would be caught and less miscarriages of justice would occur - protecting me in two ways - making me less likely to be wrongly accused or imprisoned and reducing the number of criminals on our streets thereby reducing my chances of being a victim of crime.