And there's this...
Kit Malthouse, the minister for crime and policing, said the Government was “pulling out all the stops in the battle against knife crime” and the equipment shows technology can have “an enormous impact on public safety”, adding: “No-one should feel they can walk the streets with a knife and expect to get away with it.”
Siwan Hayward, director of compliance and policing at Transport for London (TfL), said: “London’s transport network is a safe, low-crime environment and we are committed to working with the police to ensure it stays that way.
“We want to stop anyone bringing a knife or a weapon onto London’s public transport.
“This technology trial will help the police best achieve our aim.” Article
Which leads us all back to this...
Guard with jealous attention the public liberty. Suspect everyone who approaches that jewel. Unfortunately, nothing will preserve it but downright force. Whenever you give up that force, you are inevitably ruined. - Patrick Henry