Been talking to someone very much in the know. Who said that TFL draw all there data from DVLA and go by what is on there records. In his words. TFL,Vosa do not have the manpower to inspect every vehicle that enters the LEZ. Its based purely on the tracking of vehicles by camera,s and cross referencing with the DVLA,s database
Data of compliance and non compliance is taken from the DVLA database and what is actually recorded on the V5. A vehicle not subject to an m.o.t or plate cert should qualify as being exempt. And there are no lenthy time filling form filling as to why you should be operating or occupation as to why you are operating an exempt vehicle.