A view of the Russian Olympic Committee headquarters and the Russian Athletics Federation office in Moscow. (Maxim Shipenkov/European Pressphoto Agency)

The revelation that the Justice Department is looking into allegations of doping by Russian athletes seems to be the latest example of American law enforcement reaching beyond U.S. borders to target corruption — a noble effort, experts say, that nonetheless opens the country up to criticism about trying to serve as the world’s prosecutor.

In recent months, the Justice Department has assigned 10 new prosecutors to work exclusively on foreign bribery cases, while the FBI has created three squads dedicated to international corruption. The department also has proposed legislation to give prosecutors more tools to ferret out such wrongdoing.

While federal prosecutors’ efforts have long been focused on corrupt foreign businesses and elected officials — they recently announced that the Amsterdam-based telecommunications company VimpelCom had reached a deferred-prosecution agreement that required it to pay a criminal penalty of more than $230 million to the United States — they have also shown a willingness to examine wrongdoing in sports.

Prosecutors in the Eastern District of New York — where one person said the investigation of Russian doping is based — are in the midst of a massive case against high-ranking officials at FIFA, the organization responsible for the regulation of soccer worldwide.

“It’s part of our culture of wanting to bring democracy and transparency to the world,” said Andrew B. Spalding, a law professor at the University of Richmond who teaches and writes about international anti-corruption law. “We really stretch jurisdictional principles. Whether we should be doing that is an open question.”

The probe involving Russian doping, first reported by CBS News and the New York Times, appears to be in its infancy, and it is possible — perhaps even likely — that it will lead nowhere. One person familiar with the matter, speaking on the condition of anonymity to discuss an ongoing review, said among the people investigators seem to be targeting is Grigory Rodchenkov, the longtime head of Russia’s anti-doping laboratory. He told the Times that he helped Russian athletes use banned substances to get ahead in global competitions, including the Sochi Olympics, and that he did so at the direction of the Russian sports ministry.

New York lawyer Bradley D. Simon confirmed that he was representing Rodchenkov but declined to discuss his client’s allegations.

Separate from the Justice Department’s action, the International Olympic Committee announced Tuesday that dozens of former Olympic athletes could be barred from the upcoming Summer Games in Rio de Janeiro after tests of old samples revealed suspicious results for 31 athletes from 12 countries. The analysis was triggered because of the allegations about Russian athletes.

Russian leaders said they supported barring athletes who had used banned, performance-enhancing drugs in competition, but expressed bewilderment at the U.S. action.

“We are puzzled that U.S. justice decided to probe Russia,” Russian Sports Minister Vitaly Mutko told the Russian news agency TASS. “There are enough violations of anti-doping rules around the world and they can all be probed. We would like to see the United States probing its own national team. The atmosphere there is far from being cloudless.”

To bring charges related to Russian doping, federal prosecutors would need some kind of U.S. nexus — although experts said that could be relatively insignificant. Investigators are probably asking themselves whether U.S. citizens or businesses were defrauded, and whether any money passed through the U.S. financial system as a part of that, said white-collar criminal defense lawyer M. Scott Peeler of the Arent Fox law firm. Foreign companies, for example, can be investigated if their business is merely listed on a U.S. stock exchange, he said.

“They’re willing to stretch the concepts in order to go after what they truly believe to be illegal conduct that needs to be ferreted out and ended,” Peeler said.

The Russian constitution bars extradition of the country’s citizens. David B. Smith, a white-collar criminal defense lawyer at the Smith & Zimmerman firm in Alexandria, Va., said U.S. prosecutors probably would face strong legal challenges even if someone charged were to end up here.

In a forfeiture case involving a former Ukrainian official, he said he has argued against the idea that money momentarily passing through the U.S. financial system gives prosecutors jurisdiction.

“The Justice Department has become very interested in foreign matters, much more so than I think is warranted, because there’s plenty of crime here for them to bust,” he said.

But that is not to say charges would be meaningless. An indictment could make life uncomfortable for those accused of wrongdoing — allowing prosecutors to freeze their U.S. assets or issue arrest warrants that would prevent them from traveling to certain countries for fear of being taken into custody. And U.S. officials may simply wish to embarrass Russia and send a message to the world that the United States will not tolerate corruption in any form.

“The U.S. is not just trying to prosecute criminals, but it’s also trying to change worldwide cultural norms around bribery and fraud and just governance generally,” Spalding said. “These sports cases, they’re a bullhorn for the anti-corruption message, because people listen.”

Andrew Roth contributed to this report.