A federal judge ruled Monday that the Securities and Exchange Commission’s use of an in-house judge to preside over an insider-trading case was “likely unconstitutional,” a potential blow to the agency’s controversial use of its internal tribunal. The decision possibly creates a serious headache for the SEC, which is increasingly using its five administrative-law judges to hear its cases, rather than sending them to federal court, legal experts said. Although the ruling was preliminary, and won’t necessarily be duplicated in other federal courts, it could have ramifications for other SEC cases and potentially other federal agencies. More in The Wall Street Journal here.