Twitter's stock price plummeted after CEO Jack Dorsey announced that the popular microblogging platform would be banning political advertising.
Dorsey tweeted the announcement on Wednesday.
"We've made the decision to stop all political advertising on Twitter globally," he tweeted. "We believe political message reach should be earned, not bought."
"Why? A few reasons," he continued in a sequence of tweets.
"A political message earns reach when people decide to follow an account or retweet. Paying for reach removes that decision, forcing highly optimized and targeted political messages on people. We believe this decision should not be compromised by money," he explained.
He continued on to head off the possible argument that the decision would undermine free speech.
"A final note. This isn't about free expression," Dorsey explained. "This is about paying for reach. And paying to increase the reach of political speech has significant ramifications that today's democratic infrastructure may not be prepared to handle. It's worth stepping back in order to address."
Dorsey was likely pushed toward the decision by Facebook's recent and very public controversy over its policy to allow political advertisements to push what could be documented as falsehoods.
CNBC noted, on Twitter, that the company's stock fell by more than 2 percent in after-hours trading after the announcement, and at one point was as much as 4 percent lower.
Here's a news video about the announcement:
Twitter will no longer take political ads: Jack Dorsey tweets www.youtube.com