The Senate has rejected a proposal to set up special prison camps for asylum seekers with criminal records or those who refuse to cooperate with the authorities. However, it called on the government to crack down on illegal immigration.
The Senate followed the House of Representatives, which dismissed the proposal last year, arguing that the measures would contravene the European Convention on Human Rights.
The justice ministry had also come out against the plan.
The proposal, first mooted by the parliament of canton Aargau, was aimed at interning all criminal asylum seekers, or those who refuse to cooperate with the authorities.
However, in its debate on Tuesday, the Senate called on the government to consider new measures to combat illegal immigration and to speed up the repatriation of people whose asylum requests have been turned down.
Under current law, refugees have to register with the authorities on entering Switzerland and hand in their request for asylum.
The Senate ruling comes in the wake of an initiative handed in last November by the right-wing Swiss People's Party, which would make it virtually impossible for asylum seekers to gain sanctuary in Switzerland.
The initiative wants to exclude requests from people who arrived in Switzerland via a third country that is considered safe. A similar initiative by the People's Party was rejected in a nationwide vote in 1996.
Switzerland, which is not a member of the European Union, is seeking closer cooperation on asylum issues with the EU. The government wants to negotiate an agreement as part of further bilateral accords.
by Urs Geiser