12.1 The Latin expression of the doctrine is “Ex turpi causa non oritur actio,” 1 and its shorter form is used as ex turpi causa. The doctrine may apply from contract, tort and criminal laws point of view and rather than applying a single test for the ex turpi causa defence, a broad approach which takes into account the different circumstances of each case has been adopted by the Courts. 2 This chapter will define the doctrine and discuss it within the motor vehicle third party insurance context.