(Corrects reference to expelled lawyer in 8th paragraph)

Whenever police frog-march the duly elected leaders of a political party to jail for collective prosecution, alarm bells should sound. The arrest of six neofascist Golden Dawn politicians in Greece is no exception -- although in this case it may also be the least bad option for Greek authorities.

The cause for alarm is clear: The prosecution of opposition parties almost invariably represents an abuse of power for political ends, damaging the rule of law, free speech and the right of voters to representation (more than 400,000 people voted for Golden Dawn in the last elections). This kind of abuse can rip the fabric of democracy at the seams.

The Greek crackdown on Golden Dawn appears political because it happened only after the stabbing death of a left-wing rapper, Pavlos Fyssas, caused public support for Golden Dawn to drop to 7 percent from post-election highs of 11 percent. The violent nature of Golden Dawn, which has 18 members of Greece’s 300-seat Parliament, has been clear for at least two years.

So how can this nakedly political crackdown possibly be justified? The answer depends partly on the past -- Golden Dawn’s history of violence -- and partly on the future -- the government’s prosecution of the case.

Human Rights Watch and others have documented an increasingly organized campaign by Golden Dawn members in which they ride on motorcycle patrols hitting “immigrants” with clubs and iron spikes as they pass, smash the stalls of immigrant market traders, and ask dark-skinned passers-by where they are from before beating them. Yet the state seemed unwilling or powerless to prevent such crimes.

The Golden Dawn gangs have lately become more brazen and violent. This organization is not like other far-right parties that have gained a footing in other European parliaments. The views these parties promote may be repugnant, but they largely keep their activities to politics. Golden Dawn bears more resemblance to the Brownshirts who spread fear in the streets of Germany between the wars. That is neither the exercise of democratic rights nor free speech: It is crime.

All that said, the European Union and Council of Europe should press and help the Greek government to address two major concerns. First, the arrested members of Golden Dawn must receive, and be seen to receive, a fair trial. This will be a huge challenge, given their treatment by Greece’s frenzied news media. Comments such as one from Prime Minister Antonis Samaras recently in New York -- that those arrested are “a criminal group of people” -- don’t help. Nor does the reported expulsion of a lawyer from the ruling New Democracy Party for agreeing to represent a Golden Dawn defendant. Prosecutors must be able to link the arrested politicians directly to the acts of violence under investigation, including two deaths.

Second, and equally important, is that the Greek government address the root problem: racist violence and police complicity. That means changing the rhetoric of the government itself on the issue of immigrants and providing police with the training required to ensure that immigrants are protected from hate crimes. A new law on racism, which the government has said it will send to Parliament in coming days, could be a start.

The rest of Europe has yet to grasp the extreme nature of what has happened in Greece over the past six years. By the end of 2013, the Greek economy will have shrunk by 30 percent, the same proportion that the U.S. lost during the Great Depression. This is a human catastrophe, which Samaras has likened to interwar Weimar Germany. That is hyperbole that should be taken seriously.

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