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Swiss voters will this weekend cast ballots in a referendum on whether the country should automatically expel foreigners who break the law, potentially even for not disclosing income levels or libel. Opinion polls suggest the vote could go either way.

Critics of the proposal, which will be voted on Sunday by Switzerland's voting population of roughly 5.3 million, say it is "inhuman" and treats Switzerland's 2 million or so foreigners as second-class citizens.

The anti-immigration People's Party, which won national elections last fall, put forward the initiative "For the effective expulsion of foreign criminals." It is the latest referendum in Switzerland's model of democracy that gives voters a strong voice in policymaking.

In two main parts, the text lays out infractions that would qualify foreigners for expulsion. Those foreigners found guilty of heinous first-time offenses such as rape and armed robbery, will face immediate deportation after serving their sentence. Those committing generally lesser crimes could be expelled if it is their second violation within a 10-year time span.

The iron-fisted initiative, which is nearly unprecedented in Europe, has drawn striking campaign imagery.

The Swiss People's Party's website, for example, shows a white sheep atop a Swiss flag, kicking away a black sheep.

Opponents of the proposal have released an electronic advertisement next to a train station schedule board showing a tattered swastika next to a large "No" to the referendum and listing "2016 Switzerland" after 1933 Nazi Germany and 1948 in apartheid South Africa.

Recent polls suggest a tight contest at a time when Europe has been facing an influx of migrants from Syria, Iraq, Afghanistan and elsewhere.

Though Switzerland is not part of the 28-country European Union, it is in a European zone of borderless travel. As a result, it's been witness to the biggest population move in Europe since World War II.

The proposal epitomizes the growing influence of the political far-right in many parts of Europe, where anti-immigration parties, such as in France, have chalked up electoral gains amid fears about jobs and public security.

Despite its relatively low unemployment rate, Switzerland has been on a recent push to restrict access of citizens from the European Union, which all but surrounds the land-locked and generally wealthy Alpine country of 8 million. Relations with the bloc that is by far Switzerland's most important trading partner have become increasingly strained.

The effort by the People's Party amounts to an attempt to circumvent national lawmakers, who toughened rules against foreigners following previous votes on the issue in 2010 and 2012. The party insists that parliament hasn't gone far enough in implementing the will of the people.

Opponents say the measure also seeks to skirt the courts, by making expulsions an administrative formality and by stripping judges of their ability to weigh the merits of individual cases.

The federal statistics office estimates that more than 10,000 people could be affected by expulsions if the initiative passes.

The Federal Council, Switzerland's seven-person executive body, called the initiative "inhuman, because it treats the roughly 2 million foreigners who live in Switzerland as second-class citizens." It added that those who "have roots in Switzerland, like second-generation foreigners, would be penalized in particular."

Federal councilor Didier Burkhalter, who is also foreign minister, insisted there were loopholes in the measure. In a video statement, he said a housekeeper who had been residing in Switzerland for 30 years could be kicked out automatically for failing to declare her income on time, for example, while a newly arrived terrorist with no criminal record but who assembled a bomb would not be.

For the council, he said, the measure would "hit too hard for misdemeanors of lesser severity, and forget to allow for expulsion of people who plan severe crimes like a bombing or forced marriages."

But Christoph Blocher, a powerful People's Party vice president and former federal councilor, said in a published interview that the measure would still give judges some oversight but that violators would only automatically be stripped of the residency papers. He also insisted that people's voices — over politicians — must be honored.

"A power struggle is currently going on. Should the Swiss citizens or the political establishment decide?," he told Swissinfo.com, which is part of the Swiss Broadcasting Corp. "The Swiss people want something to finally be done against crimes committed by foreigners and that the victims are protected. However, the political establishment wants to decide alone."