Well, that signal group chat has also raised many questions over just how secure such messaging apps are and the risks if government officials use them on their personal devices.

Our Lisa Desjardin has more.

That's right, Jeff.

The signal chat among cabinet members has highlighted a cyber security concern, the growing use of personal phones and downloaded apps by public officials who handle sensitive information.

Attorney General Pam Bondi has dismissed calls for a criminal investigation into the signal conversation.

She says the app is secure.

Joining me now to discuss is Thomas Ridd, Professor of Strategic Studies at Johns Hopkins University.

Thomas, thanks for joining us.

Signal is an app that many folks may know is used for texting and messaging.

You just type into your phone like other ones, but can you explain why it's become the go-to

app for people handling sensitive conversations?

Signal is the most secure messaging app that we have because it is end-to-end encrypted.

So that means there's effectively a tunnel of encryption going from your phone all the way to my phone.

Should we talk via signal or text via signal? And that means anybody listening in

between, that could be signal, that could be AT&T, or somebody who owns a Wi-Fi network,

they will not be able to see our text messages and to end encrypted.

So then let's go to what the Attorney General is saying. Hear her her words last night on Fox News.

I think Signal's a very safe way to communicate.

I don't think foreign adversaries are able to hack Signal, as far as I know.

That's the question.

Are foreign adversaries able to hack into Signal?

I think it's important here to be very specific.

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