No, Leo Gallagher does not have a twin brother, Ron.
**He has a _younger brother_ , Ron.**
Both the referenced Wikipedia page and the interview page explain that.
Attorney, Greg Everts, of Quarles & Brady documents the court-case details:
> Leo Gallagher a/k/a “Gallagher” and Sold Out Shows, Inc. v. Ron Gallagher et al., Case No. 99-75657 (Eastern District of Michigan). Counsel for comedian-plaintiff in suit for trademark infringement, Lanham Act false advertising, unfair competition, and violation of right of publicity. Obtained preliminary injunction and settlement that included permanent injunctive relief.
Given the intrinsic difficulty in hoaxing a court to be a party on both sides of a dispute, the lack of motive to do so and the speculative nature of the original question, I consider this sufficient evidence to dismiss the claim that Ron and Leo Gallagher are the same person.