The nationalist governments in Poland and Hungary have also locked horns with the EU over the rule of law and climate policies.
Von Storch was referring to a brawl at a public swimming pool at the weekend in Stuttgart where police arrested three youths who had attacked staff.
Rackete had faced up to 10 years in prison on possible charges of endangering the lives of four policemen for hitting a patrol boat at the quay as she brought some 41 African migrants to land.
The study addresses "the unprecedented dilemmas confronting European states resulting from mass immigration from Africa and the Middle East."
In an earlier statement, the coast guard had said efforts were underway to reach nine missing migrants from the dinghy.
The migrant, who police did not name, was walking home in Wismar, a town on the Baltic coast.
Italy wants a United Nations arms embargo on Libya to be lifted to help the state battle people smugglers and halt the flow of migrants, Interior Minister Matteo Salvini said on Thursday.
The new law aims to punish NGOs helping illegal immigrants.
A disaster has been created in the Mediterranean. It is fueled by the relative wealth of NGOs who seek to help but who have created a cycle of chain migration and empowered smugglers.
The girl from Mainz was reported missing on May 22 and was found dead on Wednesday in a wooded area.