True Detective & True Crime

In the first episode of True Detective, Detective Marty Hart (played by Woody Harrelson) is impressed by his new partner Rust Cohle’s (Matthew McConaughey) ability to interpret the occult symbols found at a crime scene. Hart is less impressed with Cohle’s ability to suppress his confirmation bias, however.

You got a chapter in one of those books on jumping to conclusions? You attach an assumption to a piece of evidence, you start to bend the narrative to support it. Prejudice yourself.


Confirmation bias is the tendency to view the world through the filter of the conclusions you’ve already drawn. We look for information that confirms what we already believe and we ignore or minimize information that doesn’t support our conclusions. Over time, our beliefs become even more firmly entrenched. The confirmation bias reinforces the belief, and the belief reinforces the confirmation bias, and that filter gets stronger and stronger, and ever more narrow. It’s something that we do to ourselves, although we may not realize we’re doing it. We prejudice ourselves, as Marty puts its.

Confirmation bias is like bad breath: it’s easy to pick up on everyone else’s but you’re the last to know about your own. If you’re on Facebook, you probably see other people’s confirmation bias all the time, right? Think about your friends who disagree with you on, say, global warming or gun control, for example. When they post those articles with really obvious flaws in them you think, “They’re so smart about most things. How can they be so dumb about this?”

The real question, though, the hard question, is this: what am I being dumb about?

True Detective is a work of fiction, but the podcast Serial is about a real crime. It’s an enthralling and well-produced piece of longform journalism about a man named Adnan Syed who was convicted of killing his girlfriend Hae Min Lee when they were both high schoolers back in the late 90s. It’s also an extended exploration of confirmation bias. It’s clear that the show’s producer/narrator believes that the police had their confirmation bias fully engaged when they investigated Syed, but she’s also open about her own struggle with confirmation bias. She likesAdnan and believes he’s a good guy. The idea that he’s a killer doesn’t fit through her filter.

We, the audience, get to see Adnan through the producer’s filter, of course, but she has enough integrity to let the bad stuff through, too. She’s done a good job of opening that filter wide enough to let in all the evidence she can gather while at the same time not pretending to a phony level of journalistic objectivity that doesn’t exist in reality.

By telling a long story, Serial shows us something that shorter forms cannot. It shows us that confirmation bias extended over a long period of time creates a narrative. A story. And this story is important to us. Protecting that story can be a rational act of self-preservation. Consider someone who has a longstanding and heartfelt religious or political belief. They have probably built relationships with people who share their values–family, friends, a whole life built around this story. Confirmation bias isn’t just about telling yourself that you’re right, it’s about preserving your story, your entire way of life.

Letting in evidence that challenges your story is a dangerous thing. Very dangerous. Have you ever been driving and, for just a moment wondered, “What would it be like if I just jerked the wheel right now?” That’s what challenging a sincerely-held belief is like. It’s a huge risk. If you change your mind about your story, you will not only throw yourself into a state of confusion, but you will hurt your loved ones. They’ve built their lives around your story, too, and pulling the rug out from under them will not be welcome. (Can you blame them? If you’re tempted, remember that you’ve built your life around their stories, too.)

But, if you’re up for it, here are two sledghammers:

  • Ask yourself, “What evidence would convince me that this belief is not true?”
  • Take on the role of someone who disagrees with you and put together the very best argument possible against your own point of view.

And the usefulness of these techniques depends entirely on how honest you can be with yourself.