Parker Briden, the governor's press secretary, told the Kansas City Star via email that "I don't believe anyone has (Confide) downloaded on a state-issued device."
The Star then asked about the fact that the governor and most of his staff -- including Briden -- have Confide accounts connected to their personal cellphones, and whether the office has a policy about using the app. Briden did not respond.
Among those with Confide accounts are the governor's chief of staff, deputy chief of staff and a handful of other high-ranking advisers. Austin Chambers, who runs the governor's political nonprofit, and Jimmy Soni, the governor's former communications adviser who remains on Greiten's campaign payroll, also have accounts.
The use of secure messaging apps like Confide, WhatsApp and Signal is becoming more prevalent in politics, especially in the aftermath of Russian hackers' targeting Hillary Clinton and the Democratic National Committee. White House staffers reportedly used Confide to keep their communications secret until former press secretary Sean Spicer explicitly banned its use, saying it was a violation of the Presidential Records Act.
A conservative organization sued the Environmental Protection Agency earlier this year seeking texts that government workers sent using Signal, another encrypted messaging app.
Whether using these apps to conduct public business violates the state's Sunshine Law or records retention law is "a very, very tough legal question," said David Roland, director of litigation with the Freedom Center of Missouri, a Libertarian nonprofit that advocates for government transparency.
Under state law, Roland said, a record is any document or material, regardless of physical form or characteristics, made or received in connection with the transaction of official business. No record can be destroyed or disposed of, he said, unless it is determined that the record has no further administrative, legal, fiscal, research or historical value.
"The potential hitch here is that there has been almost no litigation concerning the requirements for retaining public records, and it's not clear what the penalty would be for failing to comply with the law's requirements," Roland said.
A court may determine that "vanishing texts on private phones used by public employees present a significant risk that those employees will try to avoid transparency," he said, "but that they may not have the legal tools to hold those public employees accountable for this sort of thing."
Government employees are entitled to a measure of privacy when they are not on the clock or are not dealing with public business, Roland said.