CBS News Colorado: Denver Mayor Mike Johnston and 14 of his top advisors, appointees and lawyers nicknamed themselves “Strike Force” and communicated about the city’s migrant crisis through an end-to end encryption app, CBS News Colorado has learned. The app, Signal, proceeded to automatically delete their initial conversations.

A spokesperson for Johnston said the Signal messaging was prompted by President Trump and how his administration “could have significant impacts on how Denver operates.”

The use of such messaging apps by government officials has been controversial and viewed as a way to avoid public disclosure of government decision making. In Michigan, after state police leaders were found in 2021 to be using Signal on state-issued phones, state lawmakers outlawed the use of encrypted messaging on state phones.

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