It’s no surprise that divorce is unpleasant, and many spouses want to tell the world about how awful their ex-partner is. In the past, a spouse’s ability to do this was limited. They might want to tell the whole world, but in practice they usually just told a few friends over a drink or two.

But today, it’s easy to publish a blog that can be read by anyone with Internet access. And a growing number of spouses are taking out their frustrations by putting the intimate details of their failed relationships online for everyone to see. This can be extremely unpleasant and offensive to the other spouse. But is it legal?

The law in Massachusetts is not entirely clear, but the issue came up recently in Vermont, when William Krasnansky and Maria Garrido ended their nine-year marriage. Krasnansky published a blog that included what he described as a work of fiction, but which appeared to be an account of the break-up in which he blamed Garrido for the failure of the marriage. He also scanned and published excerpts from Garrido’s diary.

Here’s what the court said:

• Krasnansky had a First Amendment right to publish the blog. He couldn’t be muzzled in advance as long as he wasn’t directly harassing Garrido or making any threats against her.
• However, he did not have the right to reproduce Garrido’s diary, since it was her property and she had a copyright in its contents.
• Third, if Krasnansky defamed Garrido, she could sue him in court for damages. (To prove defamation, Garrido would have to show that Krasnansky made false statements, as well as meeting other requirements.)

In general, while it might be tempting to go online and talk about an ex, it’s not a good idea. You might end up being sued for defamation, and your comments might come back to haunt you in a divorce case or in other ways. You might feel frustrated, but you’re much better off finding more constructive ways to channel your anger.