In England, the national DNA database has been employed to curb spitting on transit workers. As part of Operation Gobstopper, bus drivers in northwest London received 2,500 evidence collection kits. Tube staff in central London and train wardens in Scotland were similarly equipped, the BBC reported in 2004.

The kits helped prosecute about 100 people on the Tube in 2007. Reportedly, 7 out of 10 samples yielded a match to DNA profiles in the national database of criminal offenders and arrestees.

Cross-posted to Forensic Science, Statistics, and the Law