Motives for Murder

What is your starting point for writing a novel? For me, it usually starts with a picture I have in my head: in Evil for Evil, for instance, it was a skeleton shackled to a metal ring in a sea cave wall. I've no idea where it came from, but thank you to whatever Muse put it there because it gave me what I needed to start asking the questions that make a plot – why was it there, who could have put it there? And what could have happened before, to make someone do it – the whole dramatic point of the story.

Means, motive and opportunity – the classic wisdom about what the police need to establish in order to prosecute a crime. It's often the very backbone of a police procedural novel.

Only, of course, when I thought about it, motive doesn't actually form part of the necessary police evidence; maybe the prosecution will suggest one as a way to influence the jury, but for a trial to succeed it's only essential to prove that the accused was in possession of whatever was needed to commit the crime and was there at the time.

'What makes someone a killer?' is the question that interests me most in crime fiction, but it's not really 'motive' that's answers it.

There's a classic list of motives for murder, sometimes summarised as 'love, lust, lucre and loathing.' (My criminal defence advocate son would point out that getting drunk and lashing out was actually by a distance the most common.) It covers jealousy, ambition, revenge.

Yet if you look at the Shakespeare tragedies, Macbeth's motive is ambition, Hamlet's is revenge, Othello's is jealousy – all technically sufficient motives. Give Hamlet Macbeth's motive, or Othello's, and there would be no play. What gives the tragedies their absorbing interest is that each of the heroes is put into the precise position where their particular nature leaves them vulnerable.

It's the interplay of nature, nurture and circumstance that makes the killer and for all the psychological reports commissioned for the courts, in real life you can't  hope to know the full story. When it's your own character, you can – another of those god-like powers that keeps us all addicted.