Looking for a way to dodge difficult decisions? If you’re a government concerned about the Irish famine, capital punishment or the behaviour of the press, the classic answer is to set up a royal commission. We’ve had about 40 since the war: no fewer than 10 set up by Labour prime minister Harold Wilson. 'They take minutes and waste years,' he famously quipped.

A royal commission is an ad hoc advisory committee appointed by the government (in the name of the Crown) for a specific investigatory and/or advisory purpose. They’re ancient institution: it was a royal commission which in 1085 led to the creation of the Domesday Book. But they don’t always produce such clear-cut outcomes. According to one study, for the Institute for Government (IFG) thinktank, a majority of commissions take at least two years to report. At least four commissions set up between 1945 and 2000 failed to report at all. 

They include the 1964 Royal Commission on the Penal System in England and Wales, brought to an early close as it was felt that the time was 'not opportune for a single review of the penal system'. Some report but are simply ignored: The Royal Commission on Legal Services (the Benson Commission), was established in 1976 and reported in 1979, with 369 recommendations. 'It took the government four years to respond, coolly,' the IFG study notes. 

And commissions, especially if they are so-called standing commissions, can go on for a very long time indeed. The record may be held by the Royal Commission on the Ancient and Historical Monuments of Scotland, which, er, stood, from 1890 to 2015.

However indefinitely delaying the start of a promised commission, as the government appears to have done with its criminal justice plan, takes punting into the long grass to a whole new level.

As the MP and wit AP Herbert once put it: 'A government department appointing a royal commission is like a dog burying a bone – except that a dog does eventually return to the bone.'

Topics