On October 1, 1910, McNamara set off a bomb that blew up the Los Angeles Times building.

In December 1910, he helped Ortie McManigal plant a bomb at the Llewellyn iron works on the West Coast.

[4][5] Clarence Darrow, supported by Joseph Scott and Job Harriman, defended the McNamaras on behalf of the AFL.

[5][9] The AFL claimed that the McNamara brothers were innocent and that Gray Otis, owner of the Los Angeles Times, was responsible for the explosion.

[10] McNamara was an (honorary) member of the National Federation for Constitutional Liberties, founded in 1940, whose other members included: Joseph R. Brodsky, Franz Boas, Max Yergan, Tom Mooney, Marc Blitzstein, John M. Coffee, Bella Dodd, Robert W. Dunn, Dashiell Hammett, Abraham J. Isserman, Carol Weiss King, Robert Morss Lovett, Albert Maltz, Vito Marcantonio, Lewis Merrill, Jerry O'Connell, William L. Patterson, Michael Quill, Reid Robinson, George Seldes, Donald Ogden Stewart, Ella Winter, Richard Wright, and Art Young.

The guilty plea of the McNamara brothers on December 1, 1911, undercut the campaign of Job Harriman for mayor of Los Angeles, with elections only four days later.

Opposite the title page is an image of William J. Burns, captioned "The main who secured the evidence to corroborate my confession.

"[6] The McNamara papers at the University of Cincinnati include correspondence with Clarence Darrow and Upton Sinclair and photos.