It went national with the establishment of a Beta chapter (now the Harlan-McKusick Senate) at the University of South Dakota School of Law in 1904.

Delta Theta Phi now uses that name for the newsletter distributed to elected members of the administrative organization.

[2][3] Theta Lambda Phi was founded on February 18, 1903, at the law school of Dickinson College by Thomas S. Lanard and Walter P. Bishop.

The first chapter was founded as the Holmes chapter with permission of Oliver Wendell Holmes Jr. A representative of West Publishing when visiting the law school learned of the formation of the fraternity, and the next issue of the Docket (published by West) announced the organization of Theta Lambda Phi as a new national law fraternity.

Students at the Detroit College of Law, after seeing the article formed the Cooley chapter to make the fraternity national.

In November 1903, Theta Lambda Phi started The Paper Book as its official form of communication.

[10] Notable initiates of Delta Theta Phi Law Fraternity include four U.S. Presidents (Theodore Roosevelt,[7] William Taft, Calvin Coolidge, and Lyndon B. Johnson[7]), Robert Menzies, an Australian Prime Minister, nine Chief or Associate Justice of the Supreme Court of the United States, including among them Edward Douglass White Jr., Charles Evans Hughes, Oliver Wendell Holmes Jr., Harry Blackmun, John Paul Stevens, Sandra Day O’Connor, and William K. Suter, Alfred Lawrence, 1st Baron Trevethin, a Lord Chief Justice of England, 33 current or former U.S.