I’m very against this type of pervasive surveillance, but that number seems implausible. The police may have only loaded a small group of suspects into the system, only targeted specific individuals, or some other reason we’re not aware of. The police protecting some criminals wouldn’t be a departure from standard practice in the UK.

That was my first thought. They scanned roughly 1% of the UK’s population. No way they didn’t identify any wanted criminals unless the set of wanted criminals scanned for was only a tiny fraction of the overall list.