I was thinking of the Wirecard scandal in Germany. The regulators responded to concerns by silencing silencing critics of the company.

I read either "defamation" or "libel" somewhere, but this article says:

[German regulators] banned investors from betting against Wirecard shares for two months, the first such restriction on an individual company in German stock market history. That was quickly followed by a criminal complaint against two Financial Times journalists who had reported the whistleblower allegations about the payments company.

https://www.ft.com/content/f62f7f56-3d45-492c-ae88-172948d21...