It is often said that the best tribunal for an acquittal is a judge sitting alone, but the very best must be the judge sitting alone who has been bribed. Many years ago, my clients told me they had squared a judge at the Old Bailey.

When they eventually named the man they thought was in their collective pockets I was amazed. He was one of the most prosecution-minded of a generally prosecution-minded collection. If they had indeed squared him it was only to get him to reduce their sentences from 23 to 21 years (with a norm of around 15) when they and their mates went down for bank robbery after a hostile summing up.

Judges in our justice system who can be bribed may be as rare as ninetipedes, but it is by no means the case elsewhere in the western world. One of the most egregious cases was that of Chicago contract killer and enforcer Harry Aleman, whose mob-connected lawyer Robert Cooley sweetened Judge Frank Wilson. Aleman was on trial for the murder of Willie Logan, who had been beating his wife, Aleman’s cousin, and in 1972 Wilson’s fee for an acquittal was a modest $10,000.

During the late 1980s, investigators started Operation Gambat into years of corruption and mob ties within the Chicago court system, with a now penitent Cooley working for them. In February 1990 he fingered the now retired Wilson, who killed himself. There was no double jeopardy problem about retrying Aleman, ruled the court, because the first trial in front of Wilson had been a sham. This time he was convicted and sentenced to 300 years.

That was a one-off, but in 2008 two Wilkes-Barre, Pennsylvania judges, Mark Ciavarella and Michael T Conahan, pleaded guilty to accepting money from a contractor in return for imposing long sentences on juveniles to increase the numbers in the detention centres run by him. The judges were sentenced to 28 and 17.5 years respectively.

James Morton is a writer and former criminal defence solicitor