causation = performing the act that caused the offence (eg. the reason he died was cos i shot him, not cos he had a heart attack)
strict liability = mens rea does not have to be proved except when a 'reasonable and honest mistake' occurs (eg. you don't have to prove someone intended to run past a red light)
aggravating factors = factors which cause the committing of a crime to be more significant, leading to a greater punishment in sentencing. (eg. he bashed an old lady)
mitigating factors = opposite of aggravating (eg. he got bashed when he was a kid)
duress = a complete defence which states that the defendant was 'compelled' to commit the crime as he/she was in under extreme circumstances, and committed the crime in order to prevent a worse outcome (eg. i shot him before he shot my entire family)
hope this helps
. not strict definitions, but these explain those terms