But the investigators did not directly request the records from Trump's still-existing transition group, Trump for America, and instead obtained them from the General Services Administration, a separate federal agency that stored the material, according to those familiar with the Trump transition organization.
Arizona-based attorney Kory Langhofer claims Mueller's acquisition of the emails violated attorney-client privilege and the Fourth Amendment, which prohibits unreasonable searches and seizures. Spokespeople for GSA didn't immediately respond to AP's emailed requests for comment.
"It's a giant distraction", he said of Mueller's probe into Russian meddling in last year's presidential election. But he has apparently caught Michael Flynn in a lie about his lobbying activities and may have former Trump campaign manager Steve Bannon on money laundering crimes he committed before he even knew the president. He did not name the transition officials who used the devices.
The latest complaint against Mueller comes amid a barrage of criticism from Trump allies that the special counsel investigation itself is tainted on multiple fronts.
Mr Beckler was hospitalised in August and has since died.
"I seriously doubt there is anything here to taint the [Mueller] investigation", said William Jeffress, a white-collar defense attorney who represented Vice President Dick Cheney's senior aide, I. Lewis "Scooter" Libby, during the Valerie Plame CIA leak investigation.
The Wait is Over for Bon Jovi
When asked about the band's inclusion Wednesday, lead singer Jon Bon Jovi said, "I really want to say it's about time". Bon Jovi has remained active, but without guitarist Richie Sambora, who has not played with the band since 2013.
Nigeria docked points, World Cup qualification unaffected
He, however, insisted that the incident will neither affect nor distract the federation's laid down plans for the World Cup. Pinnick said: "We accept the decision of the FIFA Disciplinary Committee to fine the NFF and award the match to Algeria".
YouTube could launch a new music streaming service in March
TME Chief Executive Cussion Pang confirms : " TME and Spotify will work together to explore collaboration opportunities". Further to that, Tencent will make its own investment in Spotify by purchasing secondary shares from existing backers.
After returning from Camp David, President Trump says he's not planning to fire special counsel Robert Mueller.
Ken Nahigian, the Trump transition's executive director and trustee, said in an interview that GSA's decision to share the emails with Mueller's office would have a long-term detrimental effect for future transitions.
There are rumors around Washington suggesting Trump's firing of Mueller is imminent.
The G.S.A. helps manage the US government bureaucracy, and Trump's transition team utilized its facilities in the period between Trump's November 2016 election victory and his inauguration in January 2017. "Meanwhile, Rep. Eric Swalwell (D-CA), who sits on the House intelligence committee, dismissed the claim outright as a transparent ploy: "'Private documents' on a US Government, public email system?" he wrote on Twitter Saturday. So the president has a legitimate case to make that Mueller is on a fishing expedition - a partisan witch hunt using taxpayer dollars to do the bidding of Democrats in Congress to find evidence to impeach the president.
The special counsel's critics have seized upon the case of Peter Strzok, a senior Federal Bureau of Investigation agent whom Mueller removed from his team for sending text messages critical of Trump.
The email records are incredibly sensitive, given they include national security discussions about possible global goals for Mr Trump and contain candid assessments of candidates for top government posts.