This study demonstrated the link between the number of crime scene sample submissions (DNA crime scene stains) and the number of resulting matches with samples taken from individuals (criminal justice samples) on the United Kingdom National DNA Database (NDNADB). Data were supplied by West Midlands Police for the period from April 2000 to October 2001, representing a total 6,878 submissions and 3,982 matches. The results indicate that there was no increase in the proportion of crime scene samples matched over time. This may be because the turnover rate of criminal careers is high so that many of those on the NDNADB no longer offend. Many of those that do offend have embarked on their career so recently as to not yet appear on the NDNADB. This emphasizes the importance of taking criminal justice samples at the first available opportunity. For every 100 crime scene samples taken in the West Midlands, 58 matches are expected, which is substantially higher than national figures. There is no strong sign of diminishing returns in rates of match as the number of submitted samples increase. This is consistent with the notion of a fast-changing population of active offenders. It is concluded that criminal justice and crime scene sampling should be generic and not limited to certain categories of crime. Chronic offenders commit a wide range of crimes and do not limit themselves to any particular category of criminal activity. 3 figures, 1 note, 8 references