A group of lawyers have filed a lawsuit against the immigration policy of the German government in the Federal Constitutional Court in Karlsruhe, according to German magazine Der Spiegel.

The lawyers accuse Angela Merkel of repeatedly making decisions contrary to the German law, with opening the borders for refugees being one of the most serious ones.

"The German Chancellor has no right to overstep the boundaries of the law in the framework of her policy and exceed the powers that she has received from the voters through parliament," author of the lawsuit and Dusseldorf's attorney Clemens Antweiler said, cited by the magazine.

The lawyers demand that the court should recognize Angela Merkel's decision of September 4, 2015 as contrary to the country's constitution. The decision provided for an open-door policy for refugees and, according to Antweiler, prevented the application of the provisions of the Dublin agreement.

Merkel's refugee policy has lately been causing criticism among the German population and across the EU. According to Frontex data, more than 1.2 million migrants entered the EU in 2015, with the European Commission saying that the current immigration crisis is the biggest since the Second World War.

In Antweiler's opinion, the opening of borders is not the first of Merkel's decisions which go contrary to German and EU legislation. The lawyer also called into question the measures taken by the Chancellor while overcoming the euro crisis as well as her decision to abandon nuclear energy.