Special counsel Robert Mueller is employing more aggressive tactics in going after potentially hostile witnesses.

He has recently been stopping people of interest at US airports, and handing them subpoenas and search warrants for their devices.

Legal experts say this is not unusual, and can make it more likely witnesses will tell him the truth.



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Special counsel Robert Mueller appears to be acting more aggressively in pursuing potentially hostile witnesses, and is using a series of creative tactics that he hopes will make it more likely they will tell his team the truth, according to CNN.

In recent months, Mueller has used the power of his office to approach a number of potential witnesses at airports, surprising them with search warrants for their devices and subpoenas to make sure they don't have a chance to wipe them.

In January, Mueller surprised Lebanese-American businessman and adviser to the United Arab Emirates George Nader in precisely this way. When Nader was returning from an overseas trip, FBI agents stopped and questioned him upon arrival at Dulles International Airport near Washington, DC, and also went through his electronic devices.

Nader attended a meeting in the Seychelles in 2017 with a Russian banker and an associate of President Donald Trump, and reportedly sought to bankroll an effort to get the US to take a tough stance against Qatar. He is now reportedly cooperating with the special counsel's probe and has given Mueller critical testimony before a grand jury.

Last week, former informal adviser to the Trump campaign Ted Malloch said in a statement that he had also been stopped in a similar fashion after arriving in Boston. Malloch was also questioned and had his devices scanned, and is scheduled to appear before a grand jury later on this month.

Now, Mueller has been applying this aggressive method to Russian oligarchs arriving in the US according to multiple CNN sources, at least one of whom was stopped and questioned after arriving at a New York area airport. Mueller is reportedly looking into whether these oligarchs indirectly poured money into Trump's campaign as part of his ongoing focus on the influence of foreign money on the campaign.

None of the oligarchs Mueller is interested in have been named.

Using the crucial element of surprise

Daniel Goldman, a former federal prosecutor, said catching witnesses off-guard may be key for Mueller.

"Prosecutors and investigators like the element of surprise when you can get more instinctive (and often truthful) responses," he told CNN via text.

Michael Gerhardt, a constitutional law expert who once served as a federal special counsel, said Mueller's actions are not out of the ordinary.

"Handing people subpoenas at airports might be surprising but it is not that unusual for prosecutors to become aggressive when necessary and surprise people — how people react when surprised can be telling," he told Business Insider in an email.

Mueller's team has also recently subpoenaed the Trump Organization for documents pertaining to its dealings with Russia, and in particular its efforts to construct a Trump Tower in Moscow, despite the fact the Trump Organization had been fairly forthcoming in providing documents when they were requested.

But Jens David Ohlin, a vice dean at Cornell Law School and an expert on criminal law, previously said the power of the subpoena gives Mueller leverage.

"The broad language in the subpoena, and the requirement to comply with the subpoena, gives the prosecutor the upper hand in that negotiation," he said.

He added, "Mueller will get the documents he wants."