The new firm said in a statement it will represent "candidates, campaigns, and causes at the forefront of the conservative and center-right movement."
Its founder is Chris Gober, a lawyer for Musk's America PAC who also served as its former treasurer.
He is teaming up with Steve Roberts and Jessica Furst Johnson, who left their law firm Holtzman Vogel to join Gober as partners, the trio said on Friday.
Gober was not immediately available for comment. He told the New York Times, which reported the firm's launch early on Friday, that he wanted Lex Politica to become "synonymous with the conservative movement."