The number of cases being heard in Germany's administrative courts rose to about 320,000 in the first half of this year, from just under 69,000 the year previous, the German newspaper Neue Osnabrücker Zeitung reported.

The figure is already well in excess of the 200,000 that, in September, the Federation of German Administrative Judges (BDVR) said were expected over the course of 2017. Last year, the number of cases of migrants appealing decisions by the Federal Office for Migration and Refugees (BAMF) had already shown an increase, from some 50,000 in 2015 to about 100,000.

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Courts have been hard-pressed to deal with the number of cases, according to the administrative judge Erich Müller-Fritsche, who sits on the BDVR board. An extra 320 additional posts for administrative judges were initially announced in response to the higher number of cases, although it is estimated that some 1,000 judges would be needed to start clearing the backlog.

"The administrative courts are so heavily burdened that the work cannot be dealt with by the current staff in a timely manner," Müller-Fritsche told the newspaper. "Even the increase in personnel announced by politicians will not be enough."

The paper was reporting on an answer from the German Interior Ministry in response to a request from the opposition Left party, which blamed the government for toughening up on immigration policy in an effort to deter asylum seekers.

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"The policy of deterrence on the parts of the government has increased bureaucracy for authorities and courts," said Left party politician Ulla Jelpke. "The affected refugees, meanwhile, are being refused the protection and security that they need so desperately to become well integrated."