This was a personal accident case. It also falls under the heading of Ticket Contracts where a contract is formed on the issuing of a paper receipt or ticket as in Pay and Display car parks.
Where an automatic ticket-dispensing machine is involved, the car park operator makes the offer, in which case the placing of money in the slot is the acceptance. An alternative view is that the machine is 'a booking clerk in disguise', and that the placing of the money in the slot is the offer and the ejection of the ticket the acceptance.
So the key issues are:
1. The contract does not start until the money goes into the machine. Often parking companies try to claim the contracts starts on entry but this is quickly scotched by reference to the Thornton case.
2. The terms of the contract can be on signs, on the machine itself and on the actual ticket issued, though the latter would be questionable as they were "after the event" of forming the contract. So there is scope to use the conflict between the three sources of terms to check your liability.
What do the Parking companies say.
Usually they refer to this passage in the case.
In Thornton v Shoe Lane Parking Ltd  2 QB 163 at 170 Lord Denning MR concerned with whether a condition sought to be incorporated into the contract via a ticket issued to the person parking their car seeking to exempt the car parking company from liability for personal injury, put the matter this way – “the customer is bound by the exempting condition if he knows that the ticket is issued subject to it; or if the company did what was reasonably sufficient to give him notice of it.
They argue that they always give "reasonably sufficient notice" but a quick check of the location will show whether this is correct or not. Often the signs have been vandalised, or are unlit or do not contain the terms on which they rely. So always challenge the claim that "reasonably sufficient notice" was given.
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