Federal Interior Minister Thomas de Maizière plans on Friday to push for keeping some form of preventative detention – under which dangerous criminals are held in prison after their sentences because they are still deemed a threat to the community – at a meeting with state counterparts.

But the pro-business Free Democrats’ (FDP) justice spokesman Christian Ahrendt told Friday’s edition of daily Hamburger Abendblatt that his party would oppose any such extension by their senior coalition partners the conservative Christian Democrats (CDU).

“To re-introduce preventative detention under the label of psychological accommodation is a sham,” Ahrendt said.

It would, moreover, be rejected by courts, which deem the detention to be “retrospective” punishment, he said.

CDU general secretary Hermann Gröhe, meanwhile, warned against “abolishing good ideas hastily without urgent cause,” telling the Hamburger Abendblatt that doing away with preventative detention altogether was “absolutely without grounds.”

The European Court of Human Rights has previously branded Germany’s use of indefinite preventative detention as illegitimate. The federal cabinet then agreed to change the law so that preventative detention was limited to serious sexual and violent offenders – but with the specification that it could not be applied retrospectively. The possibility for continued detention to protect the community would instead need to be established by a court at the original time of sentencing.

Justice Minister Sabine Leutheusser-Schnarrenberger, of the FDP, has suggested that dangerous criminals be monitored after their release by electronic ankle bracelets. But many politicians both from the CDU and also from the opposition centre-left Social Democrats want dangerous prisoners instead to simply remain in jail.

Daily Berliner Morgenpost reported Friday that de Maizière planned to ask the states how they propose to deal with dangerous prisoners upon their release. He may also raise the possibility of putting prisoners who were previously in preventative detention into psychiatric institutes.