You're covering a breaking news story - a shooting, a fire, a tornado - it could be anything. Lots of media outlets are covering the same thing, so there's fierce competition to get the story first. But you also have to get it right.

The problem is, breaking news stories are typically the most chaotic and confusing to cover. And too often, media outlets in a rush to be first end up reporting things that turn out to be wrong.

For example, on Jan. 8, 2011, Rep. Gabrielle Giffords was seriously wounded in a mass shooting in Tuscon, Ariz. Some of the nation's most respected news outlets, including NPR, CNN and The New York Times, wrongly reported that Giffords had died.

And in the digital age, bad information spreads fast when reporters post erroneous updates on Twitter or social media. With the Giffords story, NPR sent out an e-mail alert saying the congresswoman had died, and NPR's social media editor tweeted the same thing to millions of Twitter followers.

So how can you work fast but ensure that you get your facts right on a big story? Here are some rules to remember:

• Be wary of eyewitness accounts. They're dramatic and make compelling copy, but in the chaos that ensues at something like a shooting, panicked bystanders aren't always reliable.

In the Giffords shooting, one eyewitness described seeing the congresswoman "slumped in the corner with an apparent gunshot wound to the head. She was bleeding down her face." At first glance, that sounds like a description of someone who has died.

In this case, fortunately, it wasn't.

• Don't report something just because another media outlet is doing so. When NPR reported that Giffords had died, other organizations followed suit.

• Never make assumptions. If you see someone who is critically injured it's easy to assume they've died. But for reporters, assumptions always follow Murphy's Law: The one time you assume you know something will invariably be the one time that assumption is wrong.

• Never speculate. Private citizens have the luxury of speculating about news events. Journalists don't, because we have a larger responsibility: To report the truth.

Getting information on a breaking story, especially one a reporter hasn't witnessed firsthand, usually involves finding out things from sources. But sources can be wrong. Indeed, NPR based its erroneous report about Giffords on bad information from sources.

So here are some questions to ask when dealing with sources on breaking news.

• Is the source absolutely in a position to know what they're telling you? In a story about a person who's been critically injured and is hospitalized, the source would have to be someone in communication with the doctors and nurses treating the victim. If they don't have that kind of access, don't go with the story.

(NPR said it reported that Giffords had died based on information from the Pima County Sheriff's department and a congressman's office. But such sources probably wouldn't have direct access to the physicians treating Giffords.)

• Is the source willing to go on the record? On-the-record sources are inherently more credible than anonymous ones.

• Can the source provide specific information? Specific details are more credible than a vague, sketchy account.

• Are multiple sources providing the same kinds of information and details? Obviously if you have five sources telling you the same story, that, on the surface at least, would seem to be more credible than just hearing the same thing from a single source. But remember, even multiple sources can be wrong, as evidenced by NPR's mistake.

In the end, perhaps the best lesson on covering the Giffords story and breaking news in general comes from The Associated Press, which refused to follow the lead of other media outlets in reporting that Giffords had died.

So how did the AP avoid making the mistake that so many others had made? AP spokesman Paul Colford said this was "because we lacked confirmation from someone w/ reason to know, such as 1st-hand knowledge."

Worth remembering.

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