Welcome to Law.com Class Actions: Critical Mass, a weekly briefing for class action and mass tort attorneys.

This week: Lawyers who specialize in mass shootings said lawsuits could be difficult over the incidents in California’s Monterey Park and Half Moon Bay. On the stand in a shareholder trial, Tesla CEO Elon Musk targeted the class action bar. As T-Mobile sought to finalize its $350 million data breach settlement, lawyers already filed new suits over another cyberattack.