Measures introduced to prevent abuses in Switzerland's labour market after it was opened to workers from the European Union in 2002 are having a positive effect.
The State Secretariat for Economic Affairs (Seco) said on Thursday that there had been a 60 per cent increase in the number of checks carried out against firms for wage-dumping.
Serge Gaillard, chief economist at the Swiss Federation of Trade Unions, said the supporting measures appeared to be working, adding that he wasn't surprised abuses of the system had been found.
The measures were introduced on June 1, 2004, to combat wage-dumping – in which foreign workers undercut local wages and prices.
These stipulated that access to Swiss jobs would be staggered through the use of quotas and that the country would have the right to impose restrictions on the number of people taking up employment until 2011.
For a limited period, Swiss-based candidates would have priority over new entrants. Similar restrictions apply to Swiss jobseekers in EU member states.
According to Seco's report, published on Thursday, 31,000 individuals were investigated between January 1 and December 31 last year.
Gaillard said the work of cantonal inspectors was crucial in curbing abuses and reminded the government of its pledge to increase their number to more than 150 nationwide.
Last year some 800 checks were carried out every month – 300 more than in 2004 – and the number of established offences increased by 16 per cent.
Last year a total of 9,600 businesses were investigated, compared with 3,500 during the last seven months of 2004.
Of those 9,600, 836 were fined – mostly in sectors which rely heavily on foreign workers such as building, catering and agriculture.
In addition, 1,327 companies were cautioned, mostly in construction. Thirteen foreign firms were banned from working in Switzerland for up to five years.
On April 1 Switzerland opened its labour market to nationals from the European Union's ten newest member states – mostly eastern European countries.
The extension of the accord between Bern and Brussels on the free movement of people came into force six months after the Swiss voted in its favour.
Ahead of the vote, supporters argued that opening up the labour market would result in economic growth, while opponents said it would lead to a flood of immigrants.
The business community, the trade unions and three of the four leading parties all came out in favour of the accord.
swissinfo with agencies
Bern and Brussels concluded a first set of bilateral treaties in 1999, which included a gradual opening up of their respective labour markets. The deal came into force in 2002.
The extension of this accord, which allows the EU's new member states to participate in the Swiss labour market and vice versa, came into effect on April 1, 2006.
The ten new EU member states joined the bloc in May 2004.
The Swiss parliament also approved a series of measures to prevent salary dumping and an undercutting of labour standards.
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