In January 2008, the Grand chamber of the European Court of Human Rights delivered its judgment in the case of E.B. v France. The case revolved around a proposed single-parent homosexual adoption. The French authorities refused to grant permission to adopt based on two grounds. Having agreed that, of the two grounds utilised by the French authorities, one had been legitimate and one illegitimate, the court turned its attention to the interconnectedness of these two grounds. The majority held that the illegitimacy of one of the grounds has the effect of contaminating the entire decision, and accordingly held in favour of the applicant. This commentary focuses on the European Court's reasoning in reaching this remarkable decision.