Last night (St. Petersburg time) I was browsing Twitter when I came across a tweet from University of Michigan economist and frequent Bloomberg contributor Justin Wolfers. He tweeted that in 48% of drivers involved in fatal crashes had blood alcohol concentrations greater than 0.16. Immediately, I was shocked. That’s a huge number. He linked to a New York Times interactive that noted “[i]n all fatal accidents involving alcohol, 48% of drivers had a blood-alcohol level higher than 0.16 percent.” That’s very different than what Wolfers tweeted so I responded to him pointing it out. The professor favorited my tweet, but when I went back to look for his original tweet, it was gone. He had deleted it.

I don’t want to pick on Wolfers here, because journalists do this all the time, but it needs to stop. Wolfers’s initial tweet had nearly a dozen retweets and a half dozen favorites when I looked at it earlier. When all of those people go back to their timeline/favorites, they will see that tweet missing and realize Wolfers deleted it. They’ll likely be a bit confused and wonder why. Maybe some will find the New York Times graphic and realize the mistake.

But many will just think something weird happened with Twitter. Worse, all of the people who read his tweet and the re-tweets of it, but didn’t retweet or favorite it themselves won’t even notice the deletion. They aren’t going to scroll back through Wolfers’s twitter and notice a missing tweet. They’ll have seen the stat and will pass it on to others as if it were true.

After I realized that Wolfers had deleted it, I tweeted at him again saying “Not a fan of you just deleting that tweet. Many people saw it but won’t notice the deletion. A correction is better, IMO.” Unfortunately, I never heard back, but I stand by what I said. Instead of deleting his error, he should have either retweeted me to note the correction or issued the correction himself. Many people who saw the initial tweet may not see the correction, but it’s better than just covering up his mistake.

Twitter is a very easy place to make errors. Journalists write things quickly and easily mix up words and facts. It’s part of the job and everyone makes mistakes more frequently than they’d like to admit. But just trying to cover up the mistake and hope no one noticed is not the way to respond when you realize something is wrong. When you have a lot of followers (Wolfers has more than 36,000), you have a responsibility to correct your mistakes.

However, there are times when I believe deleting a tweet is acceptable. Simple spelling mistakes, for instance, should be fixed. If I notice I misspell something, I quickly delete the tweet and tweet my message again with the correct spelling. Same with links that don’t work. On my blog, WordPress automatically tweets out when I publish an article, but for a while its links weren’t working. So I would immediately delete its auto-tweet and tweet my post out with the correct link. If you catch a factual error immediately after publishing a tweet (and I mean immediately!), then it’s okay to delete and tweet out the correct message. But as soon as your tweet has been out in the public and may have been seen by others, you have a responsibility to correct those factual errors and not try to cover them up.

Twitter is a very important medium for delivering news fast. That means readers believe it is factually correct, but also that it’s prone to mistakes. Readers move on quickly from tweet to tweet and rarely click on links to confirm factual information. Given all of that, it’s about time journalists have a stricter code for how they respond when they do make a mistake.