He was CNC Police which is basically a security guard with a gun at nuclear sites. He then transferred to the Met, and was quickly parachuted into an armed guard role again. He will have had basically zero investigative experienceGiving your real phone number when you're hiring your murder van seems a very basic mistake, especially for a police officer. The fact that he emailed work afterwards to say he should no longer be carrying a firearm is also interesting. Hopefully it suggests that this was his first and only victim.