A member of the Caddo Tribe of Oklahoma, Judith LeBlanc joined the Communist Party USA (CPUSA) in 1974. During the 1990s, she worked as a reporter for People’s Weekly World, a CPUSA news publication that was the forerunner of People’s World. As of March 1994, LeBlanc was a member of CPUSA’s Organization Commission. In 1998 she served on the editorial board of Political Affairs, a monthly CPUSA magazine of Marxist-Leninist theory and practice. And in 1999 she hosted the CPUSA cable television program Changing America.
In May 2002, shortly after Israel’s siege of Palestinian Authority President Yasser Arafat‘s national headquarters (as punishment for Arafat’s continuing terror war), LeBlanc traveled to Israel, the West Bank, and Gaza to report on what People’s World characterized as the Palestinian “struggle to end the Israeli occupation.” She had a very warm personal meeting with Arafat, as evidenced by this photo showing him kissing LeBlanc’s hand. Five months later, LeBlanc returned to Israel to attend that nation’s Communist Party Congress. While there, LeBlanc denounced the “crisis in the region” which had been sparked by “the Bush administration’s drive to go to war with Iraq.”
In 2005 LeBlanc was a founding member of the Anne Burlak Timpson Labor Forum, which the Massachusetts CPUSA had established and named in honor of its recently deceased party leader.
From 2005-08 LeBlanc served as a national co-chair and a steering committee member of United for Peace and Justice (UFPJ), a coalition which she had helped to establish. Afterward, she became UFPJ’s national organizing coordinator.
Circa 2007, LeBlanc was a member of the U.S. “Regional Workshop” of the Women’s International Democratic Federation, a former Soviet front. Other noteworthy members included Nydia Velazquez, Howard Dean, Angela Davis, and representatives of the International Action Center, Women for Racial and Economic Equality, Mujeres Radicales, MADRE, International ANSWER, and the Women’s International League for Peace and Freedom.
LeBlanc helped organize “Latino Congreso 2007,” a five-day event held in early October of that year to map out an action plan designed to bring out at least 10 million Latino voters in the 2008 presidential and congressional elections.
At the sixth national convention of the Committees of Correspondence for Democracy and Socialism in July 2009, LeBlanc participated in a roundtable discussion titled “Building the Left and the Progressive Majority.” That same month, she toured Australia as a guest of that nation’s Communist Party and the Australian Anti-Bases Campaign Coalition, with whom she participated in protests against joint U.S.-Australian military exercises which were taking place at the time.
Stating that “the peace movement scored an incredible victory with the  election of Barack Obama,” LeBlanc in 2009 praised the new president for “keeping his pledge that he would set a deadline, a timetable for U.S. withdrawal from Iraq”; she expressed hope that Obama would advance “our work to end the war and the occupation in Afghanistan” as well; she lauded Obama for “changing foreign policy” by improving America’s “relationship to Cuba” and forging a better “relationship to the Muslim world”; and she celebrated the new president’s understanding that “it is not only the moral responsibility of the U.S. to cut nuclear arms, but it is a necessity to move towards the abolition of nuclear weapons.”
On October 31, 2009, LeBlanc endorsed a Latinos For Peace statement calling for “no escalation of the war in Afghanistan and for expedited withdrawal of U.S. troops from Iraq and Afghanistan.” Eight months later, she addressed the “Disarm Now!” Conference at New York’s Riverside Church.
On November 29, 2010, the International Day of Solidarity with the Palestinian People, LeBlanc spoke “on behalf of civil society organizations” at a special meeting at the United Nations.
In the fall of 2011, LeBlanc became a member of the NYC General Assembly, the main decision-making body of the newly formed anti-capitalist movement, Occupy Wall Street.
As of October 2014, LeBlanc was a member of Speak Progress, the speakers bureau of the Communist Party USA.
LeBlanc has been an active leader in the movement to oppose the advancement of the Keystone XL and Dakota Access oil pipeline projects, training protesters and demonstrating alongside them.
A few days after Donald Trump’s victory in the 2016 presidential election, LeBlanc participated in “Now What? Defying Trump and the Left’s Way Forward,” a phone-in webinar organized by the Maoist-leaning Freedom Road Socialist Organization.
In June 2017 in Chicago, LeBlanc was a panelist at “The People’s Summit 2017,” an event sponsored by the Democratic Socialists of America (DSA). Her particular panel was entitled “Electoral Politics and Transformative Politics: A View from the Left.”
From August 1st through 4th, 2018, LeBlanc attended a “Mapping Socialist Strategies” conference in Briarcliff Manor, New York. Other notable attendees included Frances Fox Piven, Black Lives Matter co-founder Alicia Garza, leftist media personality Laura Flanders, International Socialist Organization member Jonah Birch, most of the DSA’s top leaders, and several affiliates of the Freedom Road Socialist Organization.
LeBlanc today is a vice-chair of CPUSA, a national field organizer for Peace Action, and chairwoman of Peace Action’s “Peace and Solidarity Commission.” She also has been a board member of “DRUM, Desis Rising Up and Moving,” an organization whose stated mission is to “build the power of immigrant workers in the U.S in unity with all workers and communities for human rights.”