I listened with interest to your interview in regards to Uber and how it has saturated your beautiful City with drivers from TfL and I fully sympathise with your issues and concerns.
While you was interviewed you stated that your licensing authority were hand tied with regards to this issue (I paraphrase) and that it was a need of change in legislation to rectify this problem.
This is not actually true, but unfortunately it is repeated several times because of the knowledge of the law and what it intended.
In the same TV program Fred Jones from Uber made a comment that the Deregulation Act 2015 is responsible, or at least a factor towards vehicles working in other areas and I am afraid that his statement is very misleading for two reasons.
1, The 2015 Act stated that jobs can be sub-contracted from one area to another.
2, Uber use cross border hiring (the triple license rule)
Reason 2 stated above is where the grey area is and your officers can actually act on this, I am sure you will talk with legal to confirm. What your officers can in fact do is charge a driver from out of town for plying for hire when they are parked waiting for jobs when they are not licensed in that area, because the intention of the triple license rule is that they should be given the booking while in the area that they are licensed and then travel to that arranged pick up.
I am more than happy to give further information including Case Law should you require.
I look forward to your reply.