The woman became suspicious after her husband set up a second email account on their home computer, according to the Aargauer Zeitung.
The couple had always known each other's passwords and had even written them down, according to the paper. Since the man used one of these passwords for his new account, his wife was easily able to access it and read his emails.
So she did – and discovered that he had been having affairs with several other women for some time.
She confronted her husband, who moved out of their apartment. He later filed a criminal complaint against his wife for reading his emails.
In February this year the Muri-Bremgarten public prosecutor issued the woman with a suspended financial penalty of 9,900 francs plus a 4,300 franc fine for her unauthorized intrusion into her husband's data, saying she deliberately and repeatedly invaded his email account and downloaded material that was not her own.
Speaking on appeal to the district court in Bremgarten, the woman's lawyer demanded acquittal for his client, saying she didn't hack into her husband's email since she knew his password.
Her search history showed that, prior to reading her husband's emails, the defendant googled whether doing so would make her liable for prosecution. This showed she knew she was entering a grey area, said the court, even though the internet did not give her a definitive answer on the subject.
The court upheld the conviction, saying unauthorized intrusion into someone else's email account is illegal, however it greatly reduced the penalty, acknowledging the woman had only shown “minimal criminal energy” since all she had to do to access the email account was to “exploit her husband's carelessness” in using the password they both knew.
Speaking to 20 Minutes, Zurich lawyer Martin Bürgi said it makes no difference whether the people involved are married, living together or don't know each other at all, someone must still have permission to read another person's messages.
Reading data protected by a password or code without the account owner's permission is illegal under article 143 of the Swiss criminal code, he said.
According to the code, such an act is punishable with a fine or up to three years in prison.