Readers of detective stories will probably familiar with the phrase motive, means and opportunity, which I will refer to as MMO-theory. The logic behind MMO-theory is simple: people will not commit a crime if they do not have a motive for doing so. Often the motive is greed, in fiction hatred also plays a role. And unfortunately too often thrill is another motive for crime.

But a motive alone is not sufficient for being suspect. One should also be able to commit a crime. For instance if one want to steal the contents of a vault, one either needs the key or some other method the break the vault. Anyone would did not have such means cannot logically be the perpetrator. Continue reading →