Definition from Nolo’s Plain-English Law Dictionary
Statutes in some states that make communications between news reporters and informants confidential and privileged, freeing journalists of the obligation to testify about them in court. This is similar to the doctor-patient, lawyer-client, or priest-parishioner privilege. The goal is to let journalists gather news without being ordered to reveal sources and notes of conversations. In states that have no shield law, many judges have found reporters in contempt of court (and given them jail terms) for refusing to name informants or reveal information gathered on the promise of confidentiality.