Due to their mental illness they didn’t know what they were doing
OR
They did not know the conduct was wrong
involuntary actions
intoxication
automatism
duress
If the person has a reasonable belief that a threat of harm exists, the threat would be carried out if the theft wasn’t committed and committing the offence is the only reasonable way to avoid harm.
duress
The persons conduct must be a reasonable response to the threat
Sudden and extraordinary emergency
E.g. someone runs into a hardware store to grab a fire extinguisher to put out a fire, but doesn’t pay for it (steals it) in the process.