It still surprises me that when you say you were a defence lawyer (nb never a criminal lawyer) how many people ask how you could defend people you knew were guilty. The great thing about defending professional criminals was that in the teeth of the evidence – caught on camera, the swag behind the fireplace, a written confession and fingerprints all over the bank counter – they would still try to explain it away. Mysterious identical twin brothers; verballed up; minding a bag for a man with red hair called Jimmy whom they met in a pub; police brutality – perm any three from four.

As for the fingerprints, my clients used to shy away from ever saying these were planted, going to the most extraordinary lengths to explain, however improbably, that their fingerprints had been found in the wrong place. In fact they might have done better to allege they had been planted.

As long ago as January 1938 David Pearce was accused of breaking into a club pavilion in Surrey. The evidence against him was that of his co-accused and a fingerprint. In his defence, Pearce demonstrated how a print could be taken and planted. He produced a small mirror and pad of a plastic substance into which he pressed the finger of a warder. He then pressed the substance on the mirror producing a perfect print. He was acquitted.

Now fingerprints are regarded with some scepticism. ‘Nothing is foolproof’ said an American prosecutor after one recent debacle. ‘Anything that has human involvement has to be questioned like any other evidence in a criminal case.’ Think of the latest magic bullet, DNA.

At least professionals, even after an acquittal, never admitted their guilt. I can recall only one man doing so. Accused of a bank robbery he swore blind he was innocent, weeping and begging, swearing on a number of relatives’ lives, some of whom were already dead. He was acquitted and then triumphantly told me afterwards that indeed he had not been the man across the counter as the police alleged, but had in fact been the getaway driver.

Curiously, he was killed in a road accident a few months later. When I heard of this I thought of Steinie Morrison, convicted of the murder of Leon Beron on Clapham Common, who always maintained he had been verballed. When he heard of the death of the inspector in his case he remarked: ‘I had become convinced there was no God but I think I shall alter my opinion after this.’