To British eyes, the business tycoon may seem to have a point in objecting to the wholesale detention in prison of those merely suspected of corruption: in this country, remand is reserved for those thought liable to abscond or commit serious offences if left at large. Even large-scale fraudsters are given bail. But Italy has an inquisitorial legal system. Preventive detention is used to allow examining magistrates to question suspects in prison. It also stops them from tampering with evidence or absconding abroad, as the Socialist leader Bettino Craxi has done.
In the Eighties, Mr Berlusconi's huge media empire showed no matching enthusiasm for the release of left-wingers being rounded up and detained on suspicion of terrorism. If he now wishes to change Italy's judicial system, he should do so through parliament, not by passing an executive decree freeing those already detained.
Mr Berlusconi's stubbornness is potentially damaging at several levels. His freshly formed party was elected in March on the back of public outrage over revelations of large-scale corruption in the old governing parties. That issue had precipitated the rise of the Northern League. It also helped to fuel the neo-Fascist resurgence. The League risks losing its raison-d'etre if it accepts the decree as it stands; and yesterday, Gianfranco Fini, leader of the National Alliance, also called on Mr Berlusconi to think again.
In the wider world, the early doubts about Mr Berlusconi's capacity to help Italy to renew itself will be reinforced. The business empire that the Italian prime minister still controls was founded on property development in Milan, then corruptly run by the Socialists. His support for this decree risks being seen as a gesture of gratitude to those who helped him on his way up.
Already four popular Milan judges who led the anti-corruption campaign have asked for a transfer to other duties. They may prove to be more in touch with public sentiment than is Mr Berlusconi.