It said this was not a violation of Branzburg or of the state constitution and talked about the rights of defendants. Because the interview wasn't confidential and there's no reason to think that this would have a chilling effect. The press has generally been unable to convince judges that it has an important interest at stake when it refuses to cooperate with people who seek nonconfidential information. The idea is that if you promised confidentially and then tell a third party you've already violated the confidentiality agreement. Some papers have special rules that forbid reporters from telling anyone outside the newspaper the name of a confidential source.
Shield laws have no bearing on federal court.
But, the protection they afford varies greatly. Some shield laws will only protect confidential sources of information, while others will protect the information itself. This act requires federal, state and local police agencies who seek journalists work product to get a subpoena rather than issue a search warrant. There are exceptions.