An explosive report written by Germany’s Bundestag Scientific Office, a team of non-partisan legal experts, has established that parliament and not Chancellor Angela Merkel should have decided on opening Germany’s borders to refugees in September 2015, writes WELT.

They refer to a ruling by the Federal Constitutional Court, on refugees reuniting with their families in Germany. The ruling stated that:

“Parliament is obliged to decide on whether, and to what extent, the proportion of non-Germans in the population will be altered by the arrival of foreigners inside the country.”

Merkel made the decision to take in thousands of refugees who were stranded in Hungary on 4 September 2015 after consulting with only the most senior members of her cabinet. Parliament never voted on it.

The opinion of the Scientific Services also indicates that the Federal Government has so far not provided any information on the legal basis for its decision. In fact, refugees from the safe third country of Austria should have been rejected at the border.

An exception to this “obligation to refuse entry” is possible in the case of “the existence of a corresponding order of the Federal Ministry of the Interior“. However, such an arrangement did not exist. Also, the so-called Selbsteintrittsrecht, with which Germany can accept asylum seekers, who should actually reside in other countries, has never been officially appealed by the federal government.

The expert report is brisant because both the FDP and the AfD have announced that after a possible entry into the Bundestag, an investigative committee on the refugee policy of Merkel will be deployed.

The Left party (Die Linke) is not so much upset by Merkel’s decision in itself, but is mainly disconcerted that Merkel and her vice-Chancellor Sigmar Gabriel had carried out the policy in such a way ‘that they strengthened the far right (AfD)’.

The annual cost of Merkel’s decision will hit 20.4 billion euros in 2020, according to the Federal Finance Ministry in a report from 2016.