IMO, no. Your defence is procedural.
I was not the owner.....
This arises because you believe that *******(the lease company) used the grounds of 'We are a vehicle-hire company etc.' in their representations and that the authority accepted the same. However, this is not permissible under the Act which restricts these grounds to, inter alia, agreements of less than 6 months: my lease is for *** years.
The authority may not consider me to be the owner and the PCN must be cancelled.
I do not dispute the facts of the contravention and therefore, should the authority reject these representations, I should be grateful if they would not belabour this point but instead focus on the grounds of my representations i.e. confirm the grounds on which the registered keeper's representations were accepted and provide the supporting mandatory documents e.g. hiring agreement etc. A signed statement of the lessee's liability under a lease would not be acceptable.
OP, I've no idea whether ****(the lease company) used the correct grounds in this case, which could ONLY be that they were not the 'keeper' (because the presumption that the registered keeper is the person by whom the vehicle is kept is rebuttable), but it's worth a punt because otherwise I cannot see a defence on the facts as we know them.
For information:
(d)that the recipient is a vehicle-hire firm ..
(i)the vehicle in question was at the material time hired from that firm under a vehicle hiring agreement.
.....
(9)In this paragraph, “vehicle hiring agreement” and “vehicle-hire firm” have the same meanings as in section 66 of the Road Traffic Offenders Act 1988 (c. 53) (Hired vehicles).
(paras. 1(4)(d) and 1(9) of Schedule 1 to the London Local Authorities etc. Act 2003 refer).
(7)This section applies to a hiring agreement under the terms of which the vehicle concerned is let to the hirer for a fixed period of less than six months (s66(7) Road Traffic Offenders Act refers)