No, MET is an unregulated private parking company.
Easy one to defeat... as long as the
unknown drivers identity is not revealed. There is no legal obligation on the
known keeper (the recipient of the Notice to Keeper (NtK)) to reveal the identity of the
unknown driver and no inference or assumptions can be made.
The location is not relevant land for the purposes of PoFA which means that if the
unknown driver is not identified, they cannot transfer liability for the charge from the
unknown driver to the
known keeper.
Use the following as your appeal. No need to embellish or remove anything from it:
I am the registered keeper. MET cannot hold a registered keeper liable for any alleged contravention on land that is under statutory control. As a matter of fact and law, MET will be well aware that they cannot use the PoFA provisions because Stansted Airport is not 'relevant land'.
If Stansted Airport wanted to hold owners or keepers liable under Airport Bylaws, that would be within the landowner's gift and another matter entirely. However, not only is that not pleaded, it is also not legally possible because MET is not the Airport owner and your 'parking charge' is not and never attempts to be a penalty. It is created for MET’s own profit (as opposed to a bylaws penalty that goes to the public purse) and MET has relied on contract law allegations of breach against the driver only.
The registered keeper cannot be presumed or inferred to have been the driver, nor pursued under some twisted interpretation of the law of agency. Your NtK can only hold the driver liable. MET have no hope at POPLA, so you are urged to save us both a complete waste of time and cancel the PCN.