Using DNA to catch offenders quicker: serious detections arising from criminal justice samples.

DNA samples on the national database matching those found at scenes of serious violent or sexual crimes were identified. The earlier offence leading the sample to appear on the database was noted. The bulk (60-84% according to inclusion criteria) involved theft, drug or other offending. The result, indicating offender versatility, is consistent with most research on criminal careers. Its importance for operational police lies in identifying the contribution made by DNA samples taken after less serious offences in clearing subsequent serious crime, and the importance of taking such samples as widely as possible. Examining specific relationships between early and later offences revealed a significant link between providing a DNA sample following a drug offence and subsequently committing murder.