Despite my 22 years as a reporter (if the definition of reporter is one who is paid for gathering news), I have never been a big fan of shield laws. The whole concept that reporters should be given special privileges goes against the concept of the reporter acting as a representative of the average citizen.
Blogger Tim Hilton of The Radical Republican also notes another problem with shield laws: When these laws are enacted we essentially have government saying who is and who is not a journalist. And the law is geared toward traditional media, because it is based on bills in other states that were written by media lobbyists:
The basic problem with reporter shield laws in general is that they amount to governmental licensing of reporters. Sen. Koster's point that the importance of courts being able to compel testimony outweighs the detriment to freedom of the press is well taken, but that is still a value judgment. He and I might think that, Jo Mannies and Steve Kraske would surely disagree. However, all four of us, and Americans in general, should be able to agree that the government should not be handing down judgments on who has the full freedom of the press and who does not.
Hilton also notes:
I concede that it bothers me to see reporters punished for refusing to reveal their sources, and I salute them for sticking to their principles. However, on principle it is clear to me that the potential harms to the free press greatly outweigh the benefits of this law.