When your defense is that the law allows you to publish garbage without fear of prosecution, one takeaway is simple: the internet is filled with garbage that needs to be well verified before you rely on it.

This blog thinks the Ninth Circuit got it right in exonerating Yelp this week from the lawsuit by a small business that was incorrectly identified in a negative Yelp ad. The decision is here.

While we feel terribly for the locksmith whose business was tarred with a brutally negative review that Yelp erroneously attached to his business, it seems clear that the court was right in deciding that Yelp was protected from prosecution by the federal Communications Decency Act.

The reasoning in Congress for this and other laws that grant safe harbor to internet facilitators of exchanges (of opinions, goods or anything else) is that if the internet sites were to be held liable for the contents of what they were portraying, the industry would shut down or need to charge a lot of money to compensate them for the risk.

As fact finders, we think the Yelp case is a handy example of why just about anything on line should be verified if you intend to make any kind of important decision based on what you read.

We recently had a case in which a negative review of a doctor became relevant in a malpractice case. Question one to us was: is this reviewer a real person and if so who is she? Based on her Yelp handle and city we managed to find her and to take a statement from her that turned out to be even more valuable than what she had posted on Yelp.

But what if “she” had turned out to be a competitor, an embittered but deranged former patient, or just a crank?

This is the not the first time we’ve written about this. In The Spokeo Lawsuit: Databases are Riddled with Errors we discussed a database that spits out some free information but then asks you to pay for more (often inaccurate) information.

As we tell our clients all the time (and as I’ve written in my book, The Art of Fact Investigation), even the most expensive databases confuse people with similar names, leave out key information such as where a person really lives or works, and are mostly hopeless with linking people and their shell companies.

The internet is a wonderful, useful and time-saving place, but there is no substitute for a good critical mind to sort investigative gold from the masses of garbage you find there.