Editor’s Note: Each week we cross-post an excerpt from Katrina vanden Heuvel’s column at the WashingtonPost.com. Read all of Katrina’s column here.

We tend to measure the influence of Rupert Murdoch’s News Corp. in terms of the reach of Fox News or the circulation of the New York Post and the Wall Street Journal. But it is actually local television stations on which Murdoch has built his empire and increased his stranglehold on access to information.

He has done so, in large part, by taking advantage of a 1999 change in FCC rules that allowed a single company to own more than one television station in the same market. That arrangement, known as a duopoly, lets big conglomerates such as News Corp. buy up stations, reduce their staffs and consolidate newsrooms. Murdoch now has nine duopolies. According to Santa Clara University’s Allen Hammond, a staggering 109 duopolies were created between 2000 and 2006.

The problem isn’t just that control over the airwaves becomes concentrated; it’s that such consolidation often results in the gutting of local news coverage. Duopoly owners tend to duplicate their local coverage and reduce the amount of airtime dedicated to community news. The subsequent lack of coverage gives local governments a free pass to operate without any real media scrutiny.

In New Jersey, for example, News Corp. owns both WWOR, northern New Jersey’s local station, and WNYW just across the river in New York. In 2009, WWOR’s only hour of local news was reduced to 30 minutes. And because so many news resources are shared between WWOR and WNYW (including, not incidentally, a co-anchor), very little of what is covered in the newscast focuses on northern New Jersey. As Sen. Frank Lautenberg (D-N.J.) complained to the New York Times, "We don’t have a reliable station within our midst."

But media and democracy groups haven’t taken that lying down.

Editor’s Note: Read all of Katrina’s column here.

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