The states that do have such laws are Alabama, Alaska, Arizona, Arkansas, California, Colorado, Delaware, Florida, Georgia, Illinois, Indiana, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Montana, Nebraska, Nevada, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, Tennessee, and the District of Columbia. Each of these states defines and applies a journalist's privilege differently. They examine who is a journalist, what kind of information the privilege protects, and whether there are any qualifications to the privilege. In addition, there is no federal shield law, though the Department of Justice does apply something akin to a shield law at the federal level. The qualifications contained in the shield laws are of critical importance to journalists, because the shield laws really provide little more protection than the common-law right to privilege. In states with shield laws, journalists actually receive more subpoenas than journalists in states without...

390-391). The shield laws suffer from other deficiencies as well. Many of them can be overcome with a judicial determination of necessity. Some states require a confidentiality agreement between a journalist and a source for the privilege to apply. Some states hold that the privilege is waived if the journalist reveals any of the confidential material, which is, in essence, waiving the privilege if the journalist reports his findings. Finally, shield laws only cover confidential communications, not what a reporter witnesses, so that a reporter can be required to testify about what a source has done in the reporter's presence. All of these qualifications make it clear that reporters may have a limited confidentiality privilege, but that such privilege is not vigorous.
References

Pember-Calvert . (2004). Mass Media Law, 2005-2006 Edition. The Mc-Graw-Hill

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