Thinking of planning your next heist? The big question is "where?". A bank is probably a pretty obvious choice but the obvious is not always the best. If this is going to be a daylight job where witnesses abound then more careful planning could save you a long time in the clink.

The Green Man suggests an amusement park. New research by the University of New South Wales indicates that happy eyewitnesses are about "as useful as tits on a bull", to quote that colourful Australian expression. Yep if you want to rely on your eye witnesses account you had better hope they are depressed, which, if they are visiting a bank these days, they probably are.

Joseph Forgas, who is professor of University of New South Wales School of Psychology, has been conducting research into this very topic and says

It shows that our recollection of past events are more likely to be contaminated by irrelevant information when we are in a positive mood. A positive mood is likely to trigger less careful thinking strategies.

Further if you are going into an exam then you had better hope you are depressed because you'll do so much better. When considering the quality and persuasiveness of arguments put by students he found that those who were in a negative frame of mind were much more lucid and coherent.

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