On March 8, 1971, the Citizens' Commission to Investigate the FBI raided an FBI "resident agency" in Media. They later released thousands of documents to major newspapers around the country. These documents revealed FBI tactics, like the recruitment of Boy Scouts as informants, and confirmed for the first time the existence of COINTELPRO, an FBI program to "expose, disrupt, misdirect, discredit, or otherwise neutralize" dissident groups in the United States.
From Wikipedia: https://en.wikipedia.org/wiki/Media,_Pennsylvania