Do criminals have to confess?

Some people think, unless criminals confess, we can have no idea what happened during a crime; we can have all sorts of theories but they will remain just theories; we can argue about these theories till the cows come home and still we would not know if any of them is true. The only way to know, according to these people, is if the criminals confess.

But people have been known to confess willingly to crimes they have not committed (as in the case of John Mark Karr confessing to the murder of Jonbenet Ramsey). When confessions are extracted through torture we have reason to doubt their veracity. But when they are offered voluntarily, are we to accept them at face value?

Crimes are sometimes complicated. More than one person could be involved. At the time the crime is occurring the participants could be at different places, unobservable by each other. In a case like this, can any of the criminals have a full picture of what happened? True, they will have a plan but will everyone be adhering to it? Criminals have a habit of doublecrossing each other. In the presence of such a tendency can we trust the confessions they provide?

How do we know whether a confession is true? How do we know what happened in a complicated case?

We can only find out by carrying out investigations--that is, by playing Sherlock Holmes.

Sherlock Holmes does not wait for criminals to confess; rather he sometimes uses what he has found out to induce criminals to confess:

“What do you wish me to do?”

“To give me a true account of all that happened at the Abbey Grange last night–-a true account, mind you, with nothing added and nothing taken off. I know so much already that if you go one inch off the straight, I’ll blow this police whistle from my window and the affair goes out of my hands forever.”

--The Abbey Grange

If we want to follow Sherlock Holmes in offering this kind of inducement we had better make sure what we have found out is largely true. Criminals are not all stupid; bluffing will work sometimes but not always.

A question arises. If Sherlock Holmes knows so much already, why does he ask for confessions? Just to tie up the loose ends? What if, in tidying up these loose ends, the criminal starts lying?

Good detectives welcome confessions and Sherlock Holmes is a good detective. Confessions voluntarily given are valuable not because they are invariably true but because sometimes they lead us to clues we have missed, thereby improving our reconstruction of what happened.

Take what criminals say always with a grain of salt, including confessions. They do not run our investigation; we do.