Stopping Bad Robocalls Act This bill requires the Federal Communications Commission (FCC) to take certain actions to protect consumers from robocalls. Specifically, the FCC must update regulations exempting certain robocalls from criminal liability to include identified parties who may make such calls, parties who may be called, and how many times they may be called; require implementation of call authentication technology; initiate a proceeding to protect called parties from one-ring scams; establish the Hospital Robocall Protection Group to develop best practices for combating robocalls made to hospitals and to devise strategies for hospitals to protect against such calls; establish a single consortium to conduct private-led robocall tracing efforts and implement a streamlined process for private entities to voluntarily share information with the FCC; ensure robocall blocking services provided on an opt-out basis are free of cost and include transparency and redress options; and provide the Department of Justice (DOJ) with evidence of any willful, knowing, and repeated robocall violation made with an intent to defraud, cause harm, or wrongfully obtain anything of value. Additionally, the bill allows a forfeiture penalty to be imposed without a prior citation where illegal robocalls were made intentionally and where inaccurate caller identification information has been provided. Further, the DOJ must assemble an interagency working group to study and report on the prohibition of robocalls with a focus on bettering enforcement against robocalls.