Sen. John Ensign (R-Nev.) is shown on Capitol Hill in this Oct. 13, 2009, file photo. FBI gets involved in Ensign affair

The Justice Department and the FBI have begun what appears to be a preliminary criminal investigation into events surrounding Sen. John Ensign’s affair with a staffer, sources tell POLITICO.

In recent days, FBI agents have contacted former aides to the Nevada Republican in Washington and Las Vegas, said several sources familiar with the matter. The sources also said that a Justice Department prosecutor has been assigned to the case but has not yet convened a grand jury.


“Yes, the FBI has contacted witnesses — in this case, former aides,” said one source familiar with the matter. “We’ll see where it leads.”

Ensign announced last summer that he had carried on a nine-month affair with campaign aide Cynthia Hampton, herself the spouse of Doug Hampton, a top Senate aide of Ensign. Since admitting to the affair, Ensign has been the subject of a series of damaging revelations about his conduct — including the fact that his parents paid the Hamptons $96,000 after the couple left their jobs with the senator.

The Senate Ethics Committee is already investigating; it issued its own subpoenas for former Ensign aides last month. But a criminal investigation raises the stakes and, whatever its outcome, could take long enough that it would hurt Ensign’s chances of winning a third term in 2012.

Ensign spokeswoman Rebecca Fisher declined Tuesday to say whether the senator has been contacted by FBI agents. “Sen. Ensign believes he has fully complied with all ethics laws and rules and plans to cooperate with any official inquiries,” Fisher said.

A Justice Department representative declined to comment.

Sources familiar with Justice Department probes say it’s unlikely that investigators have yet spoken with Ensign. Investigators typically wait to question the main players in an investigation until after they’ve built up their evidence — essentially forcing a target to choose among telling the truth, risking prosecution for making false statements or refusing to talk altogether.

While it’s not clear what the FBI agents are asking, one subject of inquiry could be Ensign’s efforts to help Doug Hampton get lobbying work after he left the senator’s office — despite a one-year ban on lobbying by former congressional aides. Another could be whether the $96,000 should have been reported as a severance payment, as required by law.

Among other former Ensign aides, the FBI has been in contact with former chief of staff John Lopez, who reportedly served as an intermediary between Hampton and Ensign after Hampton left the senator’s office. Lopez has denied that those contacts broke the law, and he has downplayed the significance of the handful of informational conversations he had with Hampton.

“Yes, they have contacted John Lopez. I don’t think he’s unique in having been contacted,” one source told POLITICO.

Robert Kelner, an attorney for Lopez, said Lopez “is well-known on Capitol Hill for integrity and professionalism. During his many years of public service, he complied with the law and worked hard for the people of Nevada.”

Melanie Sloan, head of the government watchdog group Citizens for Responsibility and Ethics in Washington, said the risk of an FBI investigation is that no one can be sure where it will lead.

“The big thing, I think, is they have opened an investigation,” Sloan said. “It’s very unlikely that they’re not going to investigate everything.”

But Sloan and other sources noted that turmoil within the Justice Department’s Public Integrity Section, which botched the corruption case against former Sen. Ted Stevens (R-Alaska) that was vacated last year, may mean that investigators would move extremely deliberately in considering whether to bring charges against a sitting U.S. senator. That section remains the most likely to take the case, particularly since the U.S. attorney in Nevada, Daniel Bogden, has signaled that he would recuse himself from any inquiry given his prior relationship with Ensign.

Peter Zeidenberg, a former official in the Public Integrity Section and now a Washington-based attorney, said cases like these may cause “angst and anxiety” within the office, but “they better be able to [handle them]; otherwise, who’s going to do it?”

After POLITICO broke the news Tuesday morning of the FBI contacts, the Democratic Senatorial Campaign Committee began a campaign targeting in-cycle Republicans, pressuring them to return campaign donations from Ensign. Brian Walsh, a spokesman for the National Republican Senatorial Committee, called the tactics “silly political games.”

Still, Chuck Muth, a GOP strategist in Las Vegas and former Nevada Republican Party executive director, said that while news of an investigation may not hurt Ensign now, it could be damaging in this year’s race to defeat Senate Democratic leader Harry Reid. Democrats and allies of Reid are already making the case that replacing a leader with a freshman will weaken Nevada’s influence, particularly because the state’s other senator is something of an outcast on the Hill.

“This will certainly hurt Nevada Republicans further, especially the GOP nominee, who will go up against Harry Reid,” said Muth, who has previously called on Ensign to step down. “The Ensign scandal is an ongoing albatross around the necks of every Republican candidate up and down the ballot.”