Congress passed the Bipartisan Campaign Reform Act (the act). The act created a new category of political advertising called electioneering communications—communications that referred to a clearly identified candidate made within 60 days of a general election or 30 days of a primary election. The act required any person making an expenditure for electioneering communication totaling more than $10,000 to disclose the identities of anyone making such an expenditure. The act also altogether banned corporations and unions from funding electioneering communications. The United States Supreme Court then held that corporations and unions could not be barred from electioneering communications unless they were the functional equivalent of express advocacy. The Court held that an ad was the functional equivalent of express advocacy only if the ad was susceptible of no reasonable interpretation other than as an appeal to vote for or against a specific candidate. The Federal Election Commission (FEC) (defendant) enacted several rules to enforce the act in line with the Court’s ruling. The FEC determined that corporations and unions would be required to disclose all donations over $1,000 that were made for the purpose of furthering electioneering communications. Congressional representative Christopher Van Hollen (plaintiff) argued that this new requirement by the FEC violated the act. Hollen argued that the act did not include a purpose requirement. The FEC countered that the act was ambiguous on this issue, and that another section of the act utilized the purpose requirement. Van Hollen countered with an argument of expressio unius est exclusio alterius, stating that Congress’s failure to include a purpose requirement in the relevant section of the act precluded the FEC from later doing so. Van Hollen also argued that the FEC’s requirement violated the act’s primary purpose of improving disclosure. The trial court agreed with Van Hollen. The appeals court reviewed the FCC’s action de novo.