[Weird Tech] DNA swabbing kits to crack down anti-social behaviour

A train operator (First North Western, which run services in Greater Manchester, Merseyside, Lancashire and Cumbria) is handing out DNA swabbing kits to its staff in an attempt to catch people who spit at them. London Police is also heading in this direction with their 'Gobstopper' operation (is this a psy-op operation of the 21st century?).

First North Western say it is part of an initiative to crack down on anti-social behaviour and improve safety for their staff. It has previously been impossible to catch or convict those responsible for spitting attacks. But with the DNA kits, saliva is taken from the victim's skin and used to search for the offender on the national DNA database.