You might want to take a look at the number of Muslims in some countries listed below, which can be found at “Muslims in EU Cities: Background research reports”
And then when cross reference that with reliable statistics, the results are not unexpected.
While Muslims represent between 4 and 5 per cent of Belgium's entire population, 35 per cent of the incarcerated population is of Muslim descent.
Denmark - about 20 percent of inmates are Muslim background.
See the original Danish here :
Of Google translation to English here:
11 percent of all prisoners in contrast to Muslims being just 3 percent of the country's population at the last census in 2001
60 to 70 percent of all inmates in the country's prison system are Muslim, according to Muslim leaders, sociologists and researchers, though Muslims make up only about 12 percent of the country's population.
Among the large number of foreign nationals held in Italian prisons are Albanians, Tunisians, Algerians and Moroccans.
The statistics show a substantial increase in the detention of immigrants particularly from Morocco, Romania, Tunisia and Nigeria in the past two years.
Spain –The government of Dubai states that that 70 percent of those in Spanish jails are Muslims, who number around 54,000.
Spain with its 40-million population, which is 94 percent Catholic, has a Muslim community of around 600,000.
None of this is surprising, as many of the charged individuals would of course only be carrying out the duties of a Muslim.
From the rape of uncovered women, and honour killings, to intafada on European streets, to extracting the jizzya from real Europeans in the form of violent criminal Jihad, to forcing the dhimmis to feel themselves subdued and humiliated. (Sura 9:29).
The question is: What is it about Muslims and why are they so obscenely over represented?
This is not the case with other immigrant groups and is a question that Muslims should indeed ponder, and attempt to find the roots of this criminality.