NEW YORK ( MainStreet) — The trickle of lawsuits that have been filed by restaurants and hotels over negative reviews posted to sites such as Yelp and TripAdvisor is about to become a torrent. That's the opinion of many experts who say this now is inevitable.

"Businesses that generate income from Yelp and TripAdvisor will be more and more aggressive about how they protect themselves," said James T. Hunt, an attorney with Slater, Tenaglia, Fritz & Hunt in New York.

"The rapid growth of online reviews has certainly led to an increase in lawsuits against reviewers," said Josh King, general counsel for legal marketplace Avvo.com, which features reviews of attorneys by clients.

Bad reviews can translate into lost revenues and that has become a prod for businesses to file suit to silence critics.

They rarely will sue the sites such as Yelp and TripAdvisor, which have significant legal protections because they are not expressing opinion. What they do is provide a venue for others to express and a body of federal law says that is protected activity.

That means the angry businesses will point their gun barrels at you, the posters.

There isn't any hiding under a pen name, either. Most review sites - possibly all -- will reveal what information they have on a poster if presented with a court order. That information generally amounts to an IP address, rarely much more, but with that and a little investigative luck, sometimes the identity of the user can be determined. And a lawsuit gets filed.

Don't you have "free speech?" Succinctly put: free speech exists in online forums but targets of that speech - hotels and restaurants are cases in point - have a right to defend themselves when subjected to defamation, which are statements that are damaging to the person or business's good reputation.

Many lawyers have traditionally shied away from defamation suits because they are not easy to win - but more of them are getting filed because, frankly, more defamation is happening.

So, exactly when do reviews trigger lawsuits?

In perhaps the most celebrated lawsuit of its kind, early this year a Fairfax, Va. jury reached a verdict in the case of contractor Christopher Dietz vs. homeowner Jane Perez . Perez had posted a Yelp review wherein she said that Dietz had botched a home improvement job and jewelry had been stolen during the work.

Dietz yelled foul, and filed suit. When the jury ruled, it said, indeed, Perez had defamed Dietz - but it added that Dietz, in various postings, had defamed her. He had sued for $750,000. The jury decided nobody was owed damages.

In Quebec City, Canada Laurent Azoulay stayed at the Hotel Quebec where, he alleged in a TripAdvisor review, he was bitten by bed bugs. The hotel responded with a suit for $95,000. That case is in Quebec's Superior Court.