It’s not clear what security precautions Clinton took when setting up her personal email account as secretary of state. In 2011, Clinton told NBC News that she had “a lot of security restraints” on her personal email use.

It’s important to know what those restraints were, said Michael Ryan, CEO of secure file transfer company South River Technologies.

“If she is just sitting down and logging into Google Mail or Hotmail over public Wi-Fi, that is much different than using a VPN to access a government server over an encrypted connection,” Ryan told NBC News. “That is something that needs to be investigated.”

CEO Michael Ryan Shares His Thoughts: Were Hillary Clinton’s Emails Safe From Hackers?