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Story highlights

Sources described an investigation that has widened to focus on possible financial crimes

The increased financial focus hasn't gone unnoticed by President Donald Trump

(CNN) —  

Federal investigators exploring whether Donald Trump’s campaign colluded with Russian spies have seized on Trump and his associates’ financial ties to Russia as one of the most fertile avenues for moving their probe forward, according to people familiar with the investigation.

The web of financial ties could offer a more concrete path toward potential prosecution than the broader and murkier questions of collusion in the 2016 campaign, these sources said.

One year after the FBI opened an investigation, the probe is now managed by special counsel Robert Mueller. Sources described an investigation that has widened to focus on possible financial crimes, some unconnected to the 2016 elections, alongside the ongoing scrutiny of possible illegal coordination with Russian spy agencies and alleged attempts by President Donald Trump and others to obstruct the FBI investigation. Even investigative leads that have nothing to do with Russia but involve Trump associates are being referred to the special counsel to encourage subjects of the investigation to cooperate, according to two law enforcement sources.

The increased financial focus hasn’t gone unnoticed by Trump, who warned Mueller, via an interview with The New York Times, that his financial dealings were a red line that investigators shouldn’t cross. But the order establishing the special counsel makes clear Mueller is authorized to investigate any matters that “arose or may arise directly from the investigation.”

In response to this CNN story, the President’s attorney, Jay Sekulow, said, “President’s outside counsel has not received any requests for documentation or information about this. Any inquiry from the special counsel that goes beyond the mandate specified in the appointment we would object to.”

In 2015, the FBI began investigating cyber breaches targeting US political organizations, including the Democratic National Committee.

In the summer of 2016, US intelligence agencies noticed a spate of curious contacts between Trump campaign associates and suspected Russian intelligence, according to current and former US officials briefed on the investigation. James Comey, in his Senate testimony, said the FBI opened an investigation into Trump campaign-Russia connections in July 2016. The strands of the two investigations began to merge.

In the months that followed, investigators turned up intercepted communications appearing to show efforts by Russian operatives to coordinate with Trump associates on damaging Hillary Clinton’s election prospects, officials said. CNN has learned those communications included references to campaign chairman Paul Manafort.

A year later, the FBI is reviewing financial records related to the Trump Organization, as well as Trump, his family members, including Donald Trump Jr., and campaign associates. They’ve combed through the list of shell companies and buyers of Trump-branded real estate properties and scrutinized the roster of tenants at Trump Tower reaching back more than a half-dozen years. They’ve looked at the backgrounds of Russian business associates connected to Trump surrounding the 2013 Miss Universe pageant. CNN could not determine whether the review has included his tax returns.

In recent weeks, investigators have also started looking into the June 2016 meeting in Trump Tower and how the White House responded to news of that meeting. The session included Trump Jr., Manafort, Trump’s senior adviser and son-in-law Jared Kushner, and a Russian attorney.

Trump has denied any collusion and maintains that his business empire has “no involvement with Russia” and that he has “no loans, no nothing” from Russia. His lawyers have detailed a few exceptions, including the Miss Universe pageant he held in Moscow and the Florida mansion he sold to a Russian oligarch in 2008. Trump earned more than $100 million from those deals, according to his lawyers.

“This is like any investigation,” says one person briefed on the probe. “You start at the core and then move to the periphery. You have to explore the finances. Where this is going is no different from any investigation.”

The Mueller Team

Since his appointment in May, Mueller has quietly gathered a team of more than three dozen attorneys, investigators and other staff in a nondescript office in Washington. Officials familiar with the probe describe it as akin to a small US attorney’s office, with FBI agents and prosecutors assigned to separate groups looking into various aspects of the investigation.

These include groups of investigators and lawyers focused separately on Russian collusion and obstruction of justice, as well as the investigations focused on Manafort and former National Security Adviser Michael Flynn, according to a US official briefed on the investigation. Some of the investigators have been pulled from field offices across the country to join the Mueller team in Washington. Others left high-paying jobs at law firms. Many of the investigators have backgrounds in investigating fraud and financial crimes. There are 16 attorneys assigned to the probe, according to a spokesman for Mueller.

The appointment of Mueller as special counsel has drawn the ire of Trump and his loyalists, who claim that the team has conflicts of interest. Trump has tweeted about the “witch hunt” more than a dozen times since Mueller was appointed. Some members of the team previously contributed to Democratic campaigns.

Mueller reports to Deputy Attorney General Rod Rosenstein, but there’s a measure of separation from Justice Department headquarters to keep the probe independent.

CNN has learned some of the investigators involved in the probe are buying liability insurance out of concern they could become targets of lawsuits from those who are being investigated, according to one of the people familiar with the probe. The Justice Department covers legal fees for employees sued in the course of their duties, but some of the lawyers want extra protection.

The Justice Department and special counsel’s office both declined to comment on the liability concerns.

Bait and Switch

The possible financial ties between Trump and Russia were part of the concerns for US intelligence and law enforcement officials from the beginning, according to one current law enforcement official and one former US intelligence official.

Over the decades, the Trump real estate business and its financial dealings have come under scrutiny by the FBI and the Justice Department multiple times.

In some cases, the FBI was pursuing others who did business with the Trump organization, including alleged mobsters who controlled key contractors used by many real estate developers in New York during the 1980s. The flow of Russian money in real estate – and concerns that some buyers were making the purchases to illegally launder money – had also drawn some attention by US authorities to the Trump business.

The international real estate business is a part of the global economy where foreigners can still use cash with fewer questions asked about the sources of money. Terrorism financing concerns long ago put more stringent rules on banking and other businesses. But the rules are looser in the business of buying and selling high-end real estate, US officials say.

Investigators are looking both at whether financial laws were broken and whether there are any dealings that could put the President or his associates in a compromising position.

“There’s always been a concern about his exposure to blackmail in his financial dealings,” says the person briefed on the investigation.

Trump has repeatedly insisted that he has no enduring financial ties to Russian interests.

But some of the people who are now under scrutiny by Mueller see a bait and switch. Instead of collusion, many believe the Mueller probe will instead end up being about past financial troubles.

“They launch an investigation into collusion in the election,” says one person whose client is among those being scrutinized by the Mueller investigators. “Then they go after people because of old business matters that have nothing to do with collusion.”

Missing Links

Even at the FBI, there’s a measure of frustration over the investigation.

After a highly contentious year investigating Hillary Clinton’s private email servers and being accused of swinging the election against her, the FBI finds itself again where officials tried not to be: amid a politically treacherous investigation that has hobbled a new President.

Worse yet, some FBI officials fear the question of whether there was any criminal coordination or collusion between the Trump campaign and Russia may never be answered.

One challenge is that tantalizing pieces of intelligence are missing key links because they did not develop long enough for investigators to determine their significance. These include intercepts monitored by US intelligence that showed suggestions of illegal coordination but nothing overt.

Those missing links mea