CalSTRS said Friday it’s joining a German shareholder lawsuit against Volkswagen over the diesel emissions scandal, adding its considerable weight in ramping up pressure on the embattled automaker.

“Volkswagen’s actions are particularly heinous, since the company marketed itself as a forward thinking steward of the environment,” said CalSTRS Chief Executive Jack Ehnes in a prepared statement. The scandal “has badly hurt the company’s value.”

CalSTRS, the California State Teachers’ Retirement System, owned $52 million in Volkswagen stock as of Dec. 31. It controls a total of $179.4 billion in assets and is the second largest U.S. public pension fund, after CalPERS.

Volkswagen admitted to the U.S. Environmental Protection Agency and California Air Resources Board last fall that it had rigged its diesel passenger cars to cheat on emissions tests. Volkswagen submitted a recall proposal to regulators but it was rejected in January by the California air board and EPA.

Numerous class action shareholder lawsuits have been filed against Volkswagen in the United States and around the world. Unlike U.S. cases, where shareholders are automatically included, CalSTRS had to “affirmatively” join the German case in order to participate in any recovery.