"Every single person in the UK should be compelled to have their DNA on the national database in an effort to prevent crime, a senior police officer has argued." - https://news.bbc.co.uk/1/hi/uk/3088920.stm
They already have some of the most extensive camera surveillance in the world. (See Rheingold's Always on Panopticon.)
Wait a second . . . how does that "prevent" crime? I can see how you might catch criminals, or exonerate suspects, but I don't get how this could be "prevention." Maybe the same way that paternity tests "prevent" pregnancy.