The U.S. Supreme Court began churning out opinions Wednesday, producing four decisions — as many as the justices have produced over the past 4 1/2 months combined.

The topics were varied, touching on subjects ranging from gun control to whistleblower protection and terrorism.

A "muddle" on guns?

In a week highlighted by the national gun control debate, the court ruled that a North Carolina man who pleaded guilty to illegal firearm possession may still appeal his conviction on constitutional grounds.

The case began on May 30, 2013, when police suspicions were aroused by a jeep illegally parked in an employees-only lot on the U.S. Capitol grounds. When owner Rodney Class returned and refused to allow a search, Capitol Police obtained a warrant and found two loaded pistols, a rifle and extra magazines of ammunition.

Questioned by the FBI at Capitol Police headquarters, Class identified himself as a "constitutional bounty hunter" and "private attorney general" who traveled the country with guns and other weapons to enforce federal law against judges whom he believed had acted illegally.

A federal grand jury indicted him on a single count of unlawfully carrying firearms on the Capitol grounds. He eventually pleaded guilty, but he later appealed the conviction, contending the law under which he was convicted is unconstitutional.

The lower courts said that by pleading guilty, he gave up his right to appeal. But on Wednesday the Supreme Court ruled that a guilty plea does not mean a citizen automatically loses his right to bring a constitutional challenge to the law under which he was prosecuted.

Justice Stephen Breyer, writing for the six-justice majority, observed that while Class, in pleading guilty, did waive his right to appeal his conviction, the plea agreement did not contain an explicit waiver of his right to bring a challenge based on his claim that the ban on weapons at the Capitol violated his Second Amendment right to keep and bear arms.

Justice Samuel Alito, joined by Justices Anthony Kennedy and Clarence Thomas, wrote a dissent four pages longer than the majority opinion. In those pages, he angrily accused the majority of creating a useless "muddle" that will "bedevil" the lower courts for years to come.

Narrowing protections for whistleblowers

In a second decision, the court ruled that whistleblower protections enacted after the 2008 financial crisis apply only to people reporting malfeasance to the Securities and Exchange Commission.

Oddly enough, the SEC, in interpreting the law, adopted a rule that provided those protections even for those who reported misconduct elsewhere, but the justices said the commission's interpretation was wrong.

The case was brought by Paul Somers, a former vice president of Digital Realty Trust Inc., a real estate investment trust that owns, develops and acquires data centers.

Somers sued the company, contending that he was fired for reporting securities law violations to senior management. He sued under the whistleblower protections of the Dodd-Frank law, which provides for damages in cases of retaliatory firing.

But writing for the Supreme Court, Justice Ruth Bader Ginsburg said that the plain language of the law applies only to those who provide pertinent information "to the Commission." Thus, a whistleblower like Somers, who reports alleged financial fraud to superiors, qualifies for damages only if he also provides that information to the SEC.

The vote was 9-0.

Collecting damages for terrorist acts

The court was also unanimous in a case involving a horrific terrorist attack in 1997. Three Hamas suicide bombings in a crowded pedestrian mall in Jerusalem resulted in five deaths and nearly 200 injuries.

U.S. citizens wounded in the attack sued Iran, claiming it was responsible because it allegedly provided material support and training for Hamas. Iran did not appear in court in the U.S., and a $71.5 million default judgment was entered in favor of those who brought the suit.

When Iran didn't pay up, the injured citizens went after property owned by Iran in the U.S., namely 30,000 ancient clay tablets and fragments housed at the University of Chicago.

The Foreign Sovereign Immunities Act of 1976 both grants and limits immunity from suit for foreign countries and their property in the U.S. In this case, the court looked at the various provisions of the statute and concluded, in an opinion written by Justice Sonia Sotomayor, that the statute does not provide a "freestanding basis" for enforcement of the judgment.

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