The Congressional Black Caucus (founded in 1971, replacing 1969’s “Democratic Select Committee”) represents the black members of the United States Congress. The moniker “conscience of the House of Representatives” has been cited in print since at least 1979 and “conscience of the Congress” has been cited in print since at least 1984.
 
Philip Aloysius Hart (1912=1976), a Democratic United States Senator from Michigan from 1959 until 1976. had been called the “consicence of the Senate” and the “conscience of the Congress.” CBC chairman Emanuel Cleaver II has written that the CBC is the “conscience of the Congress” because “the Congressional Black Caucus continuously strives to be a voice for the voiceless.”
       
 
Wikipedia: Congressional Black Caucus
The Congressional Black Caucus is an organization representing the black members of the United States Congress. Membership is exclusive to blacks, and its chair in the 112th Congress is Representative Emanuel Cleaver of Missouri.
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History
Founding
A predecessor to the caucus was founded in January 1969 as a “Democratic Select Committee"by a group of black members of the House of Representatives, including Shirley Chisholm of New York, Louis Stokes of Ohio and William L. Clay of Missouri. Black representatives had begun to enter the House in increasing numbers during the 1960s, and they had a desire for a formal organization. The first chairman, Charles Diggs, served from 1969 to 1971 and landed on the master list of Nixon political opponents for his position.
 
This organization was renamed the Congressional Black Caucus in February 1971 on the motion of Charles B. Rangel of New York. Founding members of the caucus were Shirley Chisholm, William L. Clay Sr., George W. Collins, John Conyers, Ronald Dellums, Augustus F. Hawkins, Ralph Metcalfe, Parren Mitchell, Robert Nix, Charles Rangel, Louis Stokes, and Washington D.C. Delegate Walter Fauntroy.
 
Congressional Black Caucus
From the Chairman
Dear Friend:
On behalf of the 43 members of the Congressional Black Caucus, I welcome you to our website. As we celebrate forty years of service to our nation, I am humbled and honored that my colleagues have chosen me to serve as Chair during these critical times.
 
Throughout our 40-year history, the Congressional Black Caucus has worked tirelessly to ensure that all Americans, regardless of race, color or creed have the chance to pursue and achieve the American dream.
 
Leading our communities and country with passion and commitment, the Congressional Black Caucus continuously strives to be a voice for the voiceless, earning the moniker “the conscience of the Congress.”
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Sincerely,
Emanuel Cleaver, II
 
29 December 1976, Capital Times (Madison, WI), “Hart eulogized, cremated,” pg. 4, col. 1:
MACKINAC ISLAND, Mich. (AP)—Nearly 1,000 colleagues and friends filled Washington’s St. Matthew’s Cathedral to hear the late Sen. Philip Hart of Michigan eulogized as “a gentleman of God…the conscience of the Congress.”
 
18 August 1979, Chicago (IL) Metro News, “One Step Forward, One Step Backwards,” pg. 9:
The passage of this Act (Voting Rights Act of 1965—ed.) gave rise to the formation of the Congressional Black Caucus.
 
Although we are only 17 in number, we do serve a vital role. Given the political climate in the nation at this time, our role takes an added significance. Essentially, we serve as the conscience of the House of Representatives.
   
Google Books
August 1984, Ebony magazine, pg. 46, col. 2:
While the Congressional Black Caucus has experienced setbacks, CBC members are very optimistic about its future and the impact they will have on politics and the elevation o fthe standard of living for Blacks. “The negative effects of Reaganomics have made the Caucus an even more important instrument in Black America.” says Rep. Mervyn M. Dymally (D., Calif.). “We are viewed as the conscience of the Congress on matters affecting the poor and minorities, civil rights, and excessive military expenditures.”
 
New York (NY) Times
4 Candidates Offer Platforms to the Black Caucus
By ROBIN TONER, Special to the New York Times
Published: September 27, 1987
Three Democratic Presidential contenders vied for support before an influential group of black politicians and business people today, while a fourth, the Rev. Jesse Jackson, basked in their applause.
 
At a forum sponsored by the Congressional Black Caucus this afternoon, all four candidates pledged a heightened sensitivity to civil rights, a greater commitment to education and employment programs for minorities, and a sharp reversal of United States foreign policy in Central America.
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Mr. Jackson, speaking immediately after those comments by Mr. Dukakis, said, ‘‘I will not speak to you about minorities, because you are not a minority caucus, you are the conscience of the Congress.’’
 
17 September 1989, Washington (DC) Post, “Congressional Black Caucus Facing New Circumstances After 20 Years; Succes Produces Tough Conflicts For ‘Conscience of the House’” by Tom Kenworthy, pg. A22: 
Dellums describes the group’s mandate, “the conscience of Congress.”
   
Google Books
The Crisis of Color and Democracy:
Essays on race, class, and power
By Manning Marable
Monroe, ME: Common Courage Press
1992
Pg. 148:
The Congressional Black Caucus, the conscience of the House of Representatives on budgetary policies, is curiously quiet.
 
FoxNews.com
Caucuses Rely on Racial, Ethnic Politics to Move Congress
Wednesday, November 12, 2003
By Kelley Beaucar Vlahos
Members of the Congressional Black Caucus say they are “the conscience of the Congress,” and have used the moniker most recently to explain the group’s opposition to war in Iraq and the cost of its aftermath.
 
National Review Online—Jonah Goldberg
March 31, 2006, 7:48 a.m.
Careless Caucus
Radical, unserious “leaders.”
I’m thinking of a cabal of radical legislators who don’t reflect the views of average Americans or even the interests of their own constituents. They use wedge issues, play the race card, and push their party to the ideological extreme. They collude with outside activists, many of whom use religion as a Trojan horse for a radical political agenda.

Sound like those perennial paladins of villainy, the congressional GOP? Guess again. This is the Congressional Black Caucus.
 
The caucus lives in a fantasy in which it is the “conscience of the Congress.” Immune to the sort of scrutiny that many other groups receive, it has benefited from the soft bigotry of low expectations for decades.
   
Los Angeles (CA) Times
Obama salutes black caucus as the ‘conscience’ of the U.S. Congress
September 19, 2010 |  6:54 am
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That’s why the CBC was formed – to right those wrongs; to be the conscience of the Congress. And at your first dinner, the great actor and activist, Ossie Davis, said that America was at a crossroads. And he boiled down his message about what was needed going forward to a nice little phrase. He said, “It’s not the man, it’s the plan.”
 
NYTimes.com—The Caucus
March 30, 2011, 10:11 pm
Black Caucus Celebrates 40 Years
By JADA F. SMITH
Founding and current members of the Congressional Black Caucus blew out the candles and toasted the caucus’s 40th anniversary Wednesday night in Statuary Hall in the Capitol.
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Ms. Pelosi said these victories include those for which the black caucus can share credit: Expanding voting rights, securing a national holiday in honor of the Rev. Dr. Martin Luther King Jr. and helping to diversify the Oval Office.
 
“The Congressional Black Caucus is not only the conscience of the Congress, but the conscience of the country,” she said.