Gray v Thames Trains Ltd (2009): defence of illegality
Areas of applicable law: Tort law – defence of illegality – negligence
Main arguments in this case: A claimant cannot claim damages for his own criminal behaviour
The fact of the case: The claimant sustained physical injuries in a train accident due to the negligence of the defendants which had caused the accident.
Though the claimant’s injuries were not major however he consequently suffered post-traumatic stress disorder (PTSD) from it and under this illness killed a drunken pedestrian whom he had an argument. He was later convicted of manslaughter and detained for an indefinite period in a secure hospital under section 41 of the Mental Health Act 1983. The claimant brought an action for damages for his condition of PTSD and claimed damages for loss of earnings for the period he was detained in the hospital.
The claim did not succeed on the ground of defence of illegality (ex turpi causa non oritur actio). The court held if the claimant was detained purely for his mental condition then the defence would not have applied, but here his detention was due to the criminal behaviour and it would be against the public policy to allow such claim.