The national ACLU was born during a time of social unrest in which violent police crackdowns on political protesters, labor leaders, anti-war activists and other critics of those in power were a common occurrence.

Since our inception, three years after the national ACLU was founded in 1920, we have been fighting to preserve and expand the rights guaranteed by the Bill of Rights. Labor literally brought the ACLU of Southern California into existence, with the help of radical author Upton Sinclair.

In 1923, the Los Angeles Police Department banned striking San Pedro longshoremen from holding public meetings. At a rally protesting the ban, Sinclair and five friends marched up “Liberty Hill” and tried to read aloud the First Amendment in support of the workers' rights to free speech and assembly. They continued even after the police chief warned them to "cut out that Constitution stuff," only to be arrested and charged with criminal syndicalism, or agitating to overthrow the government.

Even in the best of times, defending the right to free expression is a difficult undertaking, but in those days it took enormous courage. As Sinclair wrote to the police chief upon his release: "All I can say, sir, is that I intend to do what little one man can do to awake the public conscience, and that meantime I am not frightened by your menaces. I am not a giant physically ... I freely admit that when I see a line of a hundred policemen with drawn revolvers flung across a street to keep anyone from coming onto private property to hear my feeble voice, I am somewhat disturbed in my nerves. But I have a conscience and a religious faith, and I know that our liberties were not won without suffering, and may be lost again through our cowardice. I intend to do my duty to my country."

In the wake of the San Pedro strike, Sinclair, already a member of the newly-founded national ACLU in New York, helped to form the first ACLU affiliate here in Los Angeles.

Due in large part to Sinclair's influence, the ACLU of Southern California took an early and radical stand against worker exploitation. This no doubt inspired the Bureau of Investigation (the precursor to the FBI) to spy intensely on the ACLU of Southern California and work to obtain its membership list.