At first glance “Media Matters” is a group that monitors the wild and crazy comments that are made on radio and television. There is nothing wrong with that. People should be accountable for their words – words have power.

Since they began work in 2004, however, the watchdog spirit of the group's founding has turned into an outright assault on its political opponents. That means they delight in attacking anyone with a conservative point of view on radio or TV. In fact, they have now announced they are engaged in a “war” against Fox News Channel and anyone who appears on their airwaves. They have also admitted to engaging in a despicable campaign to dig up dirt on Fox News executives and producers in an attempt to do personal damage to people who are guilty of offering the public political perspectives they find disagreeable.

That means they have targeted me. Yes, I am paid by Fox News to do political analysis. It is also true that on most issues I am left of center – what most on the far right call a liberal. And I go to political battle over ideas and policies by offering my views, hearing other viewpoints and often challenging conservative arguments on Fox.

Yet, apparently as part of their assault on Fox and its employees, Media Matters has targeted me for years for making what they smugly and fatuously call “false claims.” They cheered as I was fired from National Public Radio last October and praised NPR’s management for their courage. Their only complaint was that NPR did not also fire my friend and Fox News colleague Mara Liasson, at the same time.

Media Matters has spent hundreds of thousands of dollars, courtesy of far-left donors like billionaire George Soros, to silence me and other media figures with whom they disagree under the guise of fighting back against the power of conservative media outlets.

But the honest way to win an argument is with ideas, facts and the power of persuasion. It is not about smearing people, playing “gotcha” over statements taken out of context and destroying news organizations.

Winning does not mean getting in the gutter by bullying sponsors in to pulling their advertising dollars from news outlets they do not like.

There are many words one could use to describe Media Matters but there is one thing they are not: liberal.

The people who run Media Matters do not believe in honest discourse or the free flow of ideas. They are in business to protect and promote one brand of political orthodoxy – far left -- by slandering and intimidating any voice in the media who disagrees with them. That is the opposite of free speech. And that means Media Matters is the opposite of liberal.

Real liberals do not try to destroy their opponents with character assassinations. Instead, they engage them in debate using facts and ideas. Real liberals favor intellect over invective. Real liberals like to win arguments by proving their case better than their opponent – they do not try to dig up dirt on executives and producers to undercut the legitimacy of media outlets that have a different editorial bent.

I am a proud liberal and secure enough in my beliefs to refrain from ad hominem attacks and dishonest cheap shots at conservatives whom I disagree with.

I cannot imagine the great liberal heroes of my life time like Thurgood Marshall, Bobby Kennedy and Daniel Patrick Moynihan having anything but contempt for liberal bullies like Media Matters. With the manic obsession of a stalker, they record and monitor every hour of broadcasting on Fox looking for examples of conservative “misinformation.”

Every news organization makes mistakes. Check the corrections box in your local daily paper if you have any questions about it. But Media Matters focuses only on people they don't agree with at news outlets and sometimes twists comments for maximum outrage as they disseminate their slanted, context-free interpretation of conservative news and commentary to politicians, pundits and sympathizers in the mainstream media.

Their tactics and view of politics are more like those of the late Senator Joseph McCarthy (R-Wis.) who zealously accused anyone who disagreed with him of being a communist or a communist sympathizer.

Media Matters is run by the credulous David Brock, a former conservative writer whose previous claim to fame was admitting that he knowingly and repeatedly lied in articles he wrote for the conservative magazine, The American Spectator, in an attempt to destroy liberals. Now, Brock makes a living in service to trying to destroy conservative news organizations.

In an op-ed for the Washington Times last week, former White House Counsel C. Boyden Gray noted that the group is allowed to receive tax-deductible contributions because of its status as a 501 (c) (3). Gray suggested that the activities of Media Matters “do not merit tax-exempt status” and that by granting them this status, the IRS “may be infringing on Fox News’ First Amendment rights.”

The IRS should seriously reconsider Media Matters’ tax status. In the meantime, the rest of us can only call them out for their dishonest and underhanded tactics. Liberals should be in the forefront of every effort to use our freedom of speech to push back against their efforts to chill, in fact destroy, the free speech of others.

Juan Williams is a writer, author and Fox News political analyst. His new book is "Muzzled: The Assault On Honest Debate" (Crown/Random House) will be released on July 26.