Note: This post is adapted from a presentation Russell Lewis, NPR’s Southern bureau chief, created on fact checking.

What is a fact?

Just because someone tells you something doesn’t mean it’s true. You also can’t trust that other sources, reporters and/or news outlets (even The New York Times) have gotten it right before you.

Trust, but verify

People don’t always intentionally get it wrong, but they often do. In every interview, a reporter should be asking their sources: “How do you know what you know?” The same goes for editors. When a reporter goes in to edit a story, he/she should be able to stand behind every fact.

And verify again

With the Internet especially, it’s very easy to “verify” facts that are actually incorrect. For example, the government agency known as the VA is not actually called the Veterans Administration.

Do your own analysis

When dealing with statistics, always try to get the raw data and do your own analysis. Don’t rely on others — even government agencies — to do the math correctly.

If a number seems suspiciously high or low, use your own “reasonableness” test. For example, if you see a statistic that claims something affects 20 million American adults, simplify that figure as 1 out of 10 adults. Does it still make sense? This exercise can help you better judge whether a claim is believable.

Never assume anything

There is no room for ambiguity when you’re talking about facts. If an editor asks you what one of our sources is talking about, you can’t say “I think she means …” Never write something you don’t understand.

Triple-check the details

Radio reporters no longer have the secret luxury of hiding misspelling in scripts. With everything also online, you have to triple-check all the details, from titles and name spellings to ages. And on that note, always ask for someone’s birthday, not their age. They may be older by the time your story is done.

Be skeptical of superlatives

If you use “biggest,” “fastest,” “longest,” “first” or “last” to describe something, you run a high risk of getting it wrong.

It’s not just on you to get it right

The people you quote also have to be accurate. Listeners and readers do not distinguish between what “we” say and what the people we interview say. If someone states a “fact” and we put it on the air or in a story, all the attribution in the world doesn’t totally absolve us if they’re wrong.

It’s important

Our audience depends on us to get it right. We have to maintain their trust and we especially can’t give them a reason to go elsewhere.

You can find a printable NPR accuracy checklist here and more examples (and cautionary tales) about the importance of fact checking in Poynter’s column “Regret the Error.”