A member of appellee Popular Democratic Party (hereafter "appellee") who was elected in the November, 1980, general election to the Puerto Rico House of Representatives from District 31, died in 1981. The Governor of Puerto Rico subsequently called for a "by-election" — open to all qualified voters in District 31 — to fill the vacancy. Appellee then filed suit in the Superior Court of Puerto Rico, alleging that the Puerto Rico statutes under which the Governor purported to act authorized only candidates and electors affiliated with appellee to participate in the by-election. Appellants, qualified electors in District 31 who are not affiliated with appellee, intervened as defendants. The court entered judgment for appellee. The Puerto Rico Supreme Court modified the Superior Court's judgment, holding, inter alia, that the pertinent statute, as properly construed, requires a by-election only if the party of the legislator vacating the seat fails to designate a replacement within 60 days after the vacancy occurs, and that, if the party selects a single candidate within such period, that candidate is declared "automatically elected to fill the vacancy." The court rejected appellants' contention that this procedure violated the Federal Constitution. While the case was pending before the Puerto Rico Supreme Court, appellee held a primary election in which only its members were permitted to participate, and which resulted in the selection of a person who, pursuant to the Supreme Court's mandate, was sworn in as the new representative from District 31.
