In summer 2019, Wieland testified as an expert witness on the PSPP case at the public hearing of the Federal Constitutional Court. He argued that PSPP is monetary policy.
In an interview with CNBC, Wieland pointed out that the impending verdict could have consequences for the Bundesbank.
Frankfurter Allgemeine Zeitung: "Zwei Wirtschaftsweise bewerten EZB-Anleihekäufe milde"
CNBC: "German court can only check German constitution"
Expert opinion of Prof. Volker Wieland on the PSPP case published as IMFS Working Paper 139 (PDF)