Officials also thought it was telling that the emails were given to WikiLeaks, which is perceived as being hostile to the U.S. government. “This wasn’t surprising to us,” said one U.S. official familiar with the investigation. 

An FBI spokesperson said in a statement Monday that the bureau was investigating the breach but declined to comment on whether political motivation was part of the inquiry. “A compromise of this nature is something we take very seriously, and the FBI will continue to investigate and hold accountable those who pose a threat in cyberspace,” the spokesperson said.

“I’m sure they will consider potential motives,” White House Spokesperson Josh Earnest told reporters on Monday.

“Manipulation is not a crime. Some would argue that Voice of America or Fox News try to manipulate elections,” one retired FBI agent told The Daily Beast.

That doesn’t mean the FBI has to remain silent if it finds evidence of Russia's meddling. Should the bureau release a statement after an investigation tying the Russians to the hack and subsequent release to Wikileaks, that would essentially be a public indictment, the officials said.

It also may be possible for the FBI to investigate the question of intent, including whether the email leak is an instance of an unregistered foreign agent illegally trying to influence the U.S. political system, another U.S. official said. But it’s easier for the FBI to investigate the breach and theft of information itself, which are clearly prohibited under U.S. law, the official added.