Democratic National Committee head Debbie Wasserman Schultz lost her job in part because of leaked emails.
It seems that we have a double standard. The email in question is about Bernie Sanders who supports Hillary Clinton. I guess it’s OK for Clinton to have an email server that could have leaked classified information, but if you are working to try to get her elected to the highest office in the U.S.A. you can't make a mistake.
If they didn't say things that were wrong, they wouldn't have to worry about keeping their email's secret.