“One of the most admirable things about our Supreme Court is the success with which its secrets have been kept. To break down this standard is a very serious offense.”

Those strong words were written by a prominent columnist by the name of Norman Hapgood. The column was published in 1921 – not 2012.

The seemingly well-sourced leaks emanating from the Supreme Court in the aftermath of the June 28 decisions in the health care cases have provoked surprised commentary from those who expect such juicy bits from the other two branches of government, but not from the secretive third: the judiciary.

But as a recent article in Slate by Jonathan Peters showed, the Court has a “long and colorful history” of leaks, including premature disclosure of how the Court would vote on big cases ranging from Scott v. Sandford to Roe v. Wade. Justices themselves have been known to tell tales out of school which, if told by anyone else, would be regarded as serious leaks.

But the all-time whopper of Supreme Court leaks came in December 1919. That is when Ashton Embry, the law clerk to Justice Joseph McKenna, resigned abruptly amid headlines that a Supreme Court insider had conspired with three Wall Street speculators to profit from knowledge about upcoming Supreme Court decisions. More than once, information Embry allegedly provided helped the financiers gain an edge by knowing which business or industry was about to be helped or harmed by a Court ruling.

It caused a sensation at the time, launching a federal investigation that included a young agent named J. Edgar Hoover. Chief Justice Edward White reportedly wept over the conspiracy. And when Embry and other co-conspirators were indicted in 1920, they lawyered up with a “dream team” that included Frank Hogan, the founder of the powerhouse law firm now known as Hogan Lovells.

But from the start, the case against Embry was flawed. The main difficulty was finding a law – rather than an ethical tradition or custom – that Embry had actually violated. Insider trading was not yet illegal then, so Embry and his co-conspirators were indicted under a shaky theory that the Court had something akin to a property right to issue its decisions according to its customs. The defendants’ legal team challenged the indictment, but it was upheld and the case remained alive.

In the end, though, the case against Embry and the others never went to trial. In 1929, the indictment was quietly dismissed, long after Embry had joined his family’s baking business and left the law behind.

John Owens, a partner at Munger, Tolles & Olsen in California, says a prosecution for the kind of leaks that may have occurred last month at the Court would be no easier now than 80-plus years ago. In 2000, Owens wrote the definitive law review article on the Embry scandal, and since then he served as head of the criminal division of the U.S. Attorney’s office in San Diego. Owens was also a Supreme Court law clerk, working for Justice Ruth Bader Ginsburg in 1997 and 1998.

Despite a modern-day code of conduct for Supreme Court clerks, Owens said “it’s an honor system” at the Court that would be hard to enforce. He figures that upwards of 60 people – clerks, justices and other Court staff – would be aware if Chief Justice John Roberts Jr. had changed his vote on the health care cases, and “if someone wants to talk, they can talk.”

As a former federal prosecutor, Owens added that “leak cases are extremely hard to prove,” and it would be hard to say that revelations about a Supreme Court decision after it was handed down would be actionable in any event.

“If these leaks did happen, it would be a betrayal of the institution, and that is very serious – but it is not a crime,” said Owens.

As for Embry, the former clerk who disgraced himself at the Supreme Court had the last word. Owens reported in his law review article that at Embry’s request, when he died in 1965, his son scattered his ashes on the grounds of the Supreme Court.

Tony Mauro can be contacted at tmauro@alm.com.