What is needed is a court ruling or an action of Congress which states that Obama is ineligible. That has never happened. Congress has ignored the issue and the courts have consistently ruled in Obama’s favor on natural born citizenship and Article II, Section 1 eligibility.
For example:
Rhodes v MacDonald, U.S. District Court Judge Clay D. Land: A spurious claim questioning the presidents constitutional legitimacy may be protected by the First Amendment, but a Courts placement of its imprimatur upon a claim that is so lacking in factual support that it is frivolous would undoubtedly disserve the public interest.U.S. District Court for the Middle District of Georgia, September 16, 2009.
Ankeny v. Daniels, Indiana (A three judge panel of the Indiana Court of Appeals ruled unanimously concerning Obama’s eligibility to receive Indiana’s Electoral votes): “Based on the language of Article II, Section 1, Clause 4 and the guidance provided by [SCOTUS in U.S. v] Wong Kim Ark, we conclude that persons born within the United States are ‘natural born citizens’ for Article II, Section 1 purposes, regardless of the citizenship of their parents.”—Indiana Court of Appeals, November 12, 2009