Via Spiegel:
What drives families to commit 'honor killings?' Who are the killers and where do they come from? A new study commissioned by the German police has found that the killers are almost always first-generation immigrants from poor backgrounds, that cases aren't increasing and that courts are making mistakes in their handling of them.
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A study by the Max Planck Institute for Foreign and International Criminal Law, which has been obtained by SPIEGEL ONLINE ahead of its release, provides the most comprehensive overview yet of so-called "honor killings" in Germany. The researchers investigated 78 cases with 109 victims and 122 perpetrators.
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The study refutes a widely-held view that the number of honor killings in Germany is increasing. While the numbers vary from year to year -- there were two in 1998 and 12 in 2004 -- the average has remained at between seven and 10 cases per year.
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Most of the victims were young. More than half were aged betweem 18 and 29. Seven percent of victims were underage, the remainder were 30 and over.
The killers tend to be older, with 32 percent aged 40 and over. Most of them -- 76 of 122 -- were of Turkish descent. People from Arab states and from the former Yugoslavia come a distant second and third.
Fewer than 10 percent of the killers were born in Germany and only 7.6 percent had German citizenship. Honor killings are hardly ever committed by second or third-generation immigrants. This, says Oberwittler, is a sign "that integration is working in Germany. The problem of honor killings is serious, but limited."(source)