FOR the average holiday-maker, this summer at Punta Ala, a classy marina on the Tuscan coast, has seemed like any other. Hundreds of elegant yachts and motorboats lie peacefully berthed sterns to jetties. For many of their owners, however, the season has been far from peaceful. As well as battling the economic crisis, they have been up against the Guardia di Finanza, the tax police.

Speaking from his holiday base in Switzerland, Mario Monti, Italy’s prime minister, said the struggle against tax evaders is “like a war” and it is “right to be tough”. A national pastime, tax evasion is put at about 18% of GDP, some €285 billion ($355 billion), making a big hole in Italy’s stretched public finances.

Fairly or unfairly, boat-owners are seen as among the rich who do not pay their share. A new tax on boat ownership and people leasing boats was introduced this year. Boats between 10 and 12 metres now incur an annual tax of €800, those between 20 and 24 metres one of €4,400, those over 64 metres €25,000. In recent weeks the tax campaign has hit marinas along Italy’s 8,000 km coast, with the Guardia di Finanza operating in plain clothes or uniform onshore.

The summer’s blitz has brought a sharp fall in business in Italian marinas. According to Roberto Fusco, chairman of Marina di Punta Ala, 20% of the boats have not been used this year and sales of fuel have fallen by 40%. The economic crisis has played a part but frequent checks, in port and at sea, have also deterred owners from manning their yachts. Some carry annual tax returns to show nosy policemen that their declared income is enough to justify ownership of a boat. Others at Punta Ala park their SUVs away from the marina and arrive on battered scooters.

Unsurprisingly, boat owners have fled to more welcoming havens. Reports talk of Italian fugitives in Corsica and Croatia. And what is true of Italians applies equally to foreigners who charter boats. Rosi Della Bruna, who runs Shaula, a yacht-services company in Rome’s marina at Ostia, says Russian visitors are not amused by Italian inquisitors. “Business is 50% down on last year, and what affects us also affects bars, restaurants, car hire, air travel and so on,” she explains. Only the year-end sums will tell if this wave of fiscal belligerence has won benefits outweighing the costs.