They are sold as safety devices, and are completely legal to sell, buy, own and use in the UK. On this basis I would say it's no less allowable than a new computer or fancy phone.
Saftey device for what though?? surely he should be teaching students to drive within the speed limits... therefore should not need one. A van driver may have the nessessity to have one... but a driving instructor...?
I've claimed for a TomTom SatNav (which just happens to have a built in GPS speed camera database) which I need to find where I'm going. The speed camera locator is a bonus Maybe your driving instructor would be better going down this route, unless already bought the snooper, in which case I'd say try it. If asked, could always say it's used to teach pupils about "safety cameras"
As this is something that comes up a lot I just had a look around the interweb to see if I could find a nice document that explains in not too complex terms the legal standing of the term and came accross this excellent AAT CPD doc... So get it quick because anytime that they realise that they've accidentally left anything in the public domain that's useful they drag it behind their members only area!
It's a word document and I've just printed my copy off (only 6 pages).
kind regards,
Shaun.
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Shaun
Responses are not meant as a substitute for professional advice. Answers are intended as outline only the advice of a qualified professional with access to all relevant information should be sought before acting on any response given.
Maybe your driving instructor would be better going down this route, unless already bought the snooper, in which case I'd say try it. If asked, could always say it's used to teach pupils about "safety cameras" 
