The president made the statement during an interview with Reuters, saying he’s worried anything he says under oath in a possible sit-down with Mueller could be used against him.
He said investigators could compare his statements with that of others who have testified in the probe, such as former FBI director James Comey.
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What is a perjury trap?
Perjury, according to Merriam-Webster Dictionary, means “voluntary violation of an oath or vow either by swearing to what is untrue or by omission.”
Toronto-based lawyer Jordon Donich broke down what exactly a “perjury trap” means: “It’s a scenario where a prosecutor calls a witness for the primary purpose of obtaining testimony in order to later prosecute that same witness for perjury, rather than, for example, legitimate investigative reasons.”
“Why it’s a trap is because you’re essentially calling a witness in order to prove they’re a liar,” Donich added.
What if Trump falls into a perjury trap?
The concept of “perjury trap” is one the president likely learned from his lawyer, Rudy Giuliani.
Giuliani expressed similar concerns during an interview with CNBC News over the weekend, saying: “I am not going to be rushed into having him testify so that he gets trapped into perjury.”
Donich explained that perjury traps aren’t as simple as the witness telling an obvious lie, as they involve skilled investigators.
“The person is not going to say, ‘The car was blue,’ then say, ‘The car was red,'” he said. “It’s not going to be that black and white.”
“The concern is that there could be a scenario where something is construed to be a lie,” the lawyer explained.
A perjury trap can be used as a form of defence in cases of perjury accusations, Donich added.
But if Trump does testify and is accused of perjury, his lawyer may not have much luck using the defence.
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According to the United States Department of Justice, it’s a defence tactic that rarely works.
“The perjury trap is a form of entrapment defense, and thus must be affirmatively proven by the defendant,” the department’s website reads. “The defense is rarely proven, even though the claim is relatively common when grand jury testimony gives rise to perjury charges.”
In this case, Donich explained Giuliani is “one step ahead” and is using the perjury trap defence even before anything has occurred.
“The lawyer is saying, ‘I know what you’re up to. We’re not going to let you do that.'”
Recent attacks against Mueller
Meanwhile, Trump has ramped up his criticism of Mueller, accusing his team of “enjoying ruining people’s lives,” and “looking to impact the election.”
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Trump’s tweets followed a New York Times report that the White House general counsel, Don McGahn, has been co-operating extensively with the special counsel team investigating Russian election meddling and potential collusion with Trump’s Republican campaign.
Over the weekend, Trump insisted his general counsel isn’t a “RAT” like former president Richard Nixon’s and accused Mueller’s team of “looking for trouble.” He contrasted McGahn with John Dean, the White House counsel for Nixon during the Watergate scandal.
Dean ultimately co-operated with prosecutors and helped bring down the Nixon presidency in 1974, though he served a prison term for obstruction of justice.
— With files from the Associated Press