Is It Illegal in Minnesota to Post a Private Email Online?

I was recently asked this question:

Is posting a private email on social media or an online website illegal? Is it illegal to forward it to a group of people?

A person emailed her elected official. She called the elected official names and used foul language. The elected official would like to forward the email to others and post the email online, probably on social media, to show the public what the other side of a poltical issue is saying about the elected official and how unreasonable and unprofessional they are. Is there anything illegal about posting a private email on the web?

Here is my answer:

Posting a Private Email Online Could Be an Invasion of Privacy

Many states recognize the tort of invasion of privacy, which includes public disclosure of private facts.

The author of the email could bring a claim that his privacy right applies to an email like this.

While such an argument may be weak, it could survive a motion to dismiss and subject the elected official who published the email to costly litigation.

Privacy Torts in Minnesota

Consider the privacy tort of public disclosure of private facts. Minnesota began recognizing the tort of invasion of privacy in 1998 in the famous Wal-Mart case.

Another legal doctrine that could be relevant is the tort of intrusion upon seclusion, which is recognized in some states. While this generally relates to property, creative attorneys could argue the tort of intrusion upon seclusion is more broad.