The nation’s high court ruled Wednesday that federal prosecutors could not use that law to charge a Florida fisherman who had thrown undersized fish back into the water to avoid an investigation.

Azamat Tazhayakov, a University of Massachusetts Dartmouth classmate of Tsarnaev, was tried and convicted in US District Court in Boston last year under a stringent obstruction of justice law that was enacted in the wake of numerous Wall Street scandals in which company officials destroyed internal records.

A college friend of accused Boston Marathon bomber Dzhokhar Tsarnaev may move to have his obstruction of justice conviction overturned, his lawyer said, after the US Supreme Court on Wednesday issued a ruling that redefined the law that prosecutors used to charge him.


That obstruction of justice charge, which the majority of justices agreed was meant to address paperwork and computers destroyed to avoid detection, provides for a tougher penalty than other obstruction laws.

Federal prosecutors in Boston used that law to charge two of Tsarnaev’s friends, who were accused of removing Tsarnaev’s backpack containing fireworks from his dorm room and throwing it in a dumpster. Tazhayakov was convicted in July 2014 and Dias Kadyrbayev pleaded guilty a month later under an agreement that he could serve seven years in prison.

US District Judge Douglas P. Woodlock had postponed sentencing until the Supreme Court could decide the fisherman’s case, known as the Yates case. The high court ruled in a 5-4 split decision Wednesday that prosecutors wrongly applied the federal law to the fisherman’s case, possibly affecting similar cases across the country.

Nicholas Wooldridge, Tazhayakov’s defense attorney, said in a telephone interview Wednesday that the majority’s ruling appears to clear the way for his client’s conviction to be thrown out, based on the argument that the law was wrongly applied. US Attorney Carmen M. Ortiz would be barred from trying Tazhayakov again under double jeopardy, he argued.


“It looks like we could be in a very good position, but until everything is said and done, I don’t want to start celebrating too soon,’’ Wooldridge said. “I would say that I am purchasing champagne, but I am not ready to open it yet.’’

In an e-mail, a spokeswoman for Ortiz said prosecutors are currently studying the US Supreme Court ruling and declined to comment.

It was not immediately clear what effect the Supreme Court ruling will have on Kadyrbayev’s case because of his decision to voluntarily admit his role. His attorney, Robert Stahl, said in a statement, “We are carefully reviewing the Supreme Court’s decision to determine its impact on the case.”

Last fall, Woodlock wrote that he would have to review Kadyrbayev’s guilty plea through the prism of the Yates decision.

“The uncertainty affects not merely the posttrial motions and sentencing in Tazhayakov but also my evaluation of the knowing and voluntary quality of the defendant Kadyrbayev’s plea,’’ Woodlock wrote last fall.

The provision of the obstruction of justice laws that Ortiz’s office used to prosecute the two friends was passed under the Sarbanes-Oxley Act of 2002, and it called for a punishment of up to 20 years in prison for the destruction of “any record, document, or tangible object” to obstruct an investigation.

The Yates case involves a Florida fisherman, John Yates, who was prosecuted after he ordered a crewman on his commercial fishing boat to throw red grouper fish back into the Gulf of Mexico after he had been ordered by a state wildlife officer to set the fish aside and return to port.


The court majority found that fish could not themselves be a “tangible object” related to a coverup.

“A fish is no doubt an object that is tangible; fish can be seen, caught, and handled, and a catch, as this case illustrates, is vulnerable to destruction,’’ Justice Ruth Bader Ginsburg wrote for the majority. “But it would cut [the federal law] from its financial-fraud mooring to hold that it encompasses any and all objects. . . . A tangible object must . . . be one used to preserve or record information.’’

Writing for the four dissenters, Justice Elena Kagan said her colleagues got it wrong.

“A person who hides a murder victim’s body is no less culpable than one who burns the victim's diary,’’ Kagan wrote. “Destroying evidence is destroying evidence, whether or not that evidence takes documentary form.’’

Wooldridge said he recently spoke with Tazhayakov, who is in the custody of the Essex County Sheriff’s Department while his case is resolved.

“It’s not all the time that I have a connection with my client,’’ Wooldridge said. “But I really do have a connection with him. He’s a good kid. He’s been in there for nearly two years, and I am excited for him to come out. He really deserves to come out of there.’’

The judge has written in court filings that the Yates decision would not affect the case of Robel Phillipos, another Tsarnaev friend who was not charged with obstruction of justice, but was convicted of lying to federal investigators. He faces up to eight years in prison when he is sentenced.


Phillipos’s lawyers said in a statement Wednesday that “we are currently reviewing the implication of the US Supreme Court’s decision. . . . We feel that the decision will have significant bearing in Robel Phillipos’s case as it relates to the materiality of the alleged false statements. The ruling also raises significant issues to be considered at sentencing.”

Milton J. Valencia can be reached at mvalencia@globe.com. John R. Ellement can be reached at ellement@globe.com.