They are among the rudders of America's conservative movement.

Names such as L. Brent Bozell III of the Media Research Center, Edwin Meese III of the Heritage Foundation, Tony Perkins of the Family Research Council, Lt. Gen. (Ret.) William Boykin of the Family Research Council, Mat Staver of Liberty Counsel and Michael Farris of Alliance Defending Freedom.

They are the ones media seek out for comment on important issues of the day.

Now they collectively are sending a message to establishment media: Stop using the "hit pieces" from the Southern Poverty Law Center in your reporting.

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Forty-seven individuals and groups in a coalition Wednesday released an open letter to news outlets, calling on them to stop using data from the "discredited Southern Poverty Law Center."

WND reported recently a campaign by SPLC to silence a conservative Alabama state Supreme Court justice is backfiring, with a federal court ordering his counter-suit to continue.

WND also has reported that several organizations, claiming SPLC has smeared them with its "hate" designation, have filed lawsuits.

Get the Whistleblower Magazine's revelations about the SPLC, in its March 2015 edition of "The Hate Racket," the complete story of how one group fools government into equating Christians and conservatives with Klansmen and Nazis – and rakes in millions doing it.

SPLC also has been linked to domestic terror, in the attack by Floyd Corkins on FRC headquarters in Washington, and the recent attempt by James Hodgkinson to assassinate Rep. Steve Scalise and other Republicans.

SPLC had slammed Scalise for his political views, and Hodgkinson had "liked" the SPLC on Facebook.

Other individuals and organizations who have signed the letter to media regarding SPLC include Frank Gaffney and Clare Lopez of the Center for Security Policy, Brad Dacus of the Pacific Justice Institute, Frank Wright of D. James Kennedy Ministries, Scott Walter of the Capital Research Center, David Barton of WallBuilders, David Yerushalmi and Robert Muise of the American Freedom Law Center, Martin Mawyer of the Christian Action Network, Tim Wildmon and Sand Rios of the American Family Association, and Joseph Farah, founder and CEO of WND.com

An announcement about the letter explains SPLC "has recklessly labeled dozens of mainstream conservative organizations as 'hate groups.'"

The letter states: "We are writing to you as individuals or as representatives of organizations who are deeply troubled by several recent examples of the media's use of data from the Southern Poverty Law Center (SPLC). The SPLC is a discredited, left-wing, political activist organization that seeks to silence its political opponents with a 'hate group' label of its own invention and application that is not only false and defamatory, but that also endangers the lives of those targeted with it."

It was in June when SPLC supporter James Hodgkinson shot Scalise, R-La.; Zach Barth, a staff member for Rep. Roger Williams; former congressional staff member Matt Mika; and two U.S. Capitol Police officers at a practice for a charity baseball game.

SPLC had demonized Scalise for promoting white supremacy and inferred "that Rep. Scalise is a so-called 'hater.'"

The FRC attacker, Corkins, cited SPLC as his inspiration for his going to the Washington offices of the Family Research Council, armed with a gun, intending to kill as many people as he could. He was stopped by a security guard, who was injured.

Both Liberty Counsel and D. James Kennedy Ministries have gone to court over SPLC's charge they are "hate" organizations.

SPLC has been so extreme it also got into trouble with the Disciplinary Counsel in the Office of the General Counsel of the Department of Justice under President Obama.

There, SPLC lawyers were sharply rebuked and reprimanded for employing its "hate group" on a conservative advocacy group. The counsel stated that using SPLC’s map "overstepped the bounds of zealous advocacy and was unprofessional." It continued that such behavior is "uncivil" and "constitutes frivolous behavior and does not aid the administration of justice."

Just days ago, talk radio superstar Rush Limbaugh criticized SPLC as "perhaps one of the biggest hate groups on the left."

"They tar and feather and slander right-wing groups and call them hate groups," he said. "They've got a map on their website, and whenever a right-wing group that says or does anything that the Southern Poverty Law Center, which is a bunch of leftist freaks, all you have to do is disagree with them and you are called a hater."

The new letter explains: "We believe the media outlets that have cited the SPLC in recent days have not intended to target mainstream political groups for violent attack, but by recklessly linking the Charlottesville melee to the mainstream groups named on the SPLC website – those that advocate in the courts, the halls of Congress, and the press for the protection of conventional, Judeo-Christian values – we are left to wonder if another Floyd Lee Corkins will soon be incited to violence by this incendiary information."

It continued: "To associate public interest law firms and think tanks with neo-Nazis and the KKK is unconscionable, and it represents the height of irresponsible journalism to do so. All reputable news organizations should immediately stop using the SPLC descriptions of individuals and organizations based on the SPLC's obvious political prejudices."

The letter charges: "The SPLC is an attack dog of the political left. … [It] has realized the profitability of defamation, churning out fundraising letters, and publishing 'hit pieces' on conservatives to promote its agenda and pad its substantial endowment (of $319 million). Anyone who opposes them, including many Protestants, Catholics, Jews, Muslims, and traditional conservatives is slandered and slapped with the 'extremist' label or even worse, their 'hate group' designation.

"At one point, the SPLC even added Dr. Ben Carson to its 'extremist' list because of his biblical views (and only took him off the list after public outcry)."

The letter points out the experts who share these concerns.

"Laird Wilcox, one of America's foremost genuine experts on political extremist organizations, has said of the SPLC: 'What they do is a kind of bullying and stalking. They pick people who are vulnerable in terms of public opinion and simply destroy them.'"

The Army disassociated from SPLC materials, and the FBI removed the SPLC from a list of trusted resources on its "Hate Crimes" page.

"We wonder," the letter said, "how the media would react if a corresponding situation arose on the center-right of the political spectrum. For example, let's assume that congressional debate were raging as to whether or not taxpayers should continue to fund Planned Parenthood, which receives about $500 million a year from Congress. If a national pro-life advocacy organization were to release a map with caricatures of abortionists and title it, 'Here's Where the Baby Killers are Located in Your State,' would the media run the story? Would it reprint the map and discuss the location of these 'pro-death' doctors throughout the news day? Clearly, it would not."

The Parker case arose when SPLC complained to state officials in Alabama about his comments in an interview on American Family Radio. The state began an investigation and he responded with a lawsuit charging such efforts violate the First Amendment.

A federal court now has ordered a trial on his concerns.

Get the Whistleblower Magazine's revelations about the SPLC, in its March 2015 edition of "The Hate Racket," the complete story of how one group fools government into equating Christians and conservatives with Klansmen and Nazis – and rakes in millions doing it.

SPLC's agenda also has been criticized as "incredible" by Rev. Franklin Graham, CEO and president of both Samaritan's Purse and the Billy Graham Evangelistic Association.

"A hate group? Can you believe this – the Southern Poverty Law Center in Montgomery, Ala., has labeled a number of Christian groups such as D. James Kennedy Ministries, and the Family Research Council run by my good friend Tony Perkins as 'hate' groups. Why?" he wrote on a Facebook post.