recklessness, categories of Two categories of recklessness in criminal law may be discerned. 1. Cunningham-type defendant knows the risk, is willing to take it and takes it deliberately. 2. Caldwell-type defendant performs an act which creates an obvious risk, and, when performing the act, he has either given no thought to the possibility of such a risk arising or he recognised that some risk existed, but went on to take it. (There is no such offence as murder by recklessness ).