1) Break it down.

Let’s say you have to fact-check the following sentence:

Donald Trump took the oath of office on Thursday, Jan. 17, 2017, wearing a blue tie.

The first thing a fact-checker would notice is that there isn’t just one claim of fact in that sentence; there are many! A fact-checker would verify that:

  • Donald Trump did take the oath of office. (He was sworn in, right?)
  • Trump took the oath of office on Jan. 17, 2017. (That’s the right day, month, year?)
  • Jan. 17, 2017, was a Thursday. (Not a Wednesday or a Friday?)
  • Trump was wearing a blue tie as he took the oath of office. (It wasn’t red? Magenta? Multi-colored?)

Breaking down sentences like this helps you to determine not just everything you’ll need to verify, but also the many ways in which a simple sentence could be wrong. In this case, there are three errors.

  • Trump took the oath of office on Jan. 20, 2017.
  • Jan. 20 was a Friday.
  • Trump was wearing a red tie.

I’ve found that mistakes often happen in the nooks and crannies of sentences, where there are claims you might overlook. You might check that Trump took the oath of office on a particular date, but don’t confirm which day of the week it was. I call these bone-headed mistakes, and they can happen if you aren’t being careful.

2) Determine where to look.

Each claim is different, and requires you to ask: where could I look to verify it?

The claims about Trump are easily checked in newspaper accounts and videos of the event. I used articles in The New York Times, The Washington Post and The Wall Street Journal (news organizations you can generally trust on basic matters of fact) to determine when Trump took the oath of office, and video from PBS to check the color of his tie.

But what about different sorts of claims, like scientific or historical ones? Generally, I go straight to the experts. Are there books or papers written by scholars on the topic? Can I access them online? Have magazines that publish in-depth and fact-checked reporting, like The New Yorker, run articles on the topic?

If I suspect I’ll be able to find relevant information on a given website, I often use a site-specific search to look up an exact phrase or name. That kind of search is more refined than simply typing related terms into Google.

3) Read around the topic and find the debate.

But if the claim is general, it’s often most useful to start reading around the topic you’re looking into. I sometimes start on Wikipedia. (Yes, that’s OK!) Those articles have footnotes, and the footnotes can guide further reading and research.

Even if what I’m looking up is specific — a claim, say, about the history of poll watching and voter intimidation — I’ll often immerse myself in the debate about the topic. The debate could be scholarly, like researchers disagreeing about the implications of a study, or more obviously political. Often it’s somewhere in between. But reading around the topic and getting immersed in the debate is the only way to sharpen your judgment about which claims are based on good evidence and which ones aren’t. The key is to know enough to be able to distinguish a reliable source from an unreliable one.

When I first started fact-checking at a magazine, before I joined Retro Report, it took me a while to wrap my head around this concept: There’s no ultimate arbiter of facts out there. There’s no secret bible with every conceivable fact laid out and indexed for easy consultation. There’s no special equation that tells you whether a claim is True with a capital T. To be an effective fact-checker, you need to learn how to find good evidence, know when you have enough of it, and most important, know when you don’t.

This is how you inoculate yourself against misinformation.

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