It was almost two months ago that we first wrote about the New York City District Attorney’s office issuing Twitter with a subpoena demanding the release of tweets and account information from an Occupy Wall Street protestor who had been arrested.

Twitter contested the original motion, saying that tweets are owned by the users, not the company, but a judge has now ruled that there would be no privacy violation if the material were to be handed over. The American Civil Liberties Union had previously commended Twitter for their defense of free speech rights, but it now seems that this was all in vain.

Explaining his decision to demand that Twitter hands over tweets from Malcolm Harris, Judge Matthew Sciarrino wrote:

“If you post a tweet, just like if you scream it out the window, there is no reasonable expectation of privacy.”

Judge Sciarrino did also say that he would personally review the information provided by Twitter and only release sections to the prosecution and defense lawyers that were pertinent to the case – not all of the available content.

You can read more of the legal discussion about this case in the original BBC article, but the salient point to take away from this is that whatever you say on an open social network such as Twitter is considered to be public information – and it can be used as evidence in court.

If you want to broadcast a message that will reach a wide audience, then using a service like Twitter is a great idea. However, if you are unsure of how that message may be received then using a private sharing network would be a smarter choice.