Seven years ago, Twitter began its rise to prominence by billing itself as a space where people could speak freely because nobody was censored. The company's rules enshrined this ideal, promising "we do not actively monitor and will not censor user content, except in limited circumstances." But in 2015 all of that changed.

There were changes in Twitter's rules here and there before 2015, usually to make it easier for the company to ban people engaging in spam and fraud. But as more high-profile Twitter users began to experience abuse and harassment firsthand, the company began to reverse its earlier policies.

Writing for Motherboard, legal analyst Sarah Jeong offers a short history of how Twitter's rules changed over the year. Without ever touching the language in its rules page, Twitter began to add links out to other documents that explained the "limited circumstances" that could lead to censorship.

In March, the company banned revenge porn. In April, they banned any speech that could incite terrorism, or violence against people "on the basis of race, ethnicity, national origin, religion, sexual orientation, gender, gender identity, age, or disability."

Essentially, writes Jeong, they banned hate speech.

Jeong continues:

When asked for comment, a Twitter spokesperson contested this characterization, saying the company does not prohibit hate speech. “‘Hateful conduct’ differs from ‘hate speech’ in that the latter focuses on words. It’s the incitement to violence that we're prohibiting. Offensive content and controversial viewpoints are still permitted on Twitter.” Twitter is correct in that their definition of “hateful conduct” does not span quite as broadly as the hate speech prohibited in many European jurisdictions. But given that a viewpoint-based restriction on inciting speech is something that’s alien to American law, and the “hateful conduct” classification looks just like a subset of hate speech, it seems a bit like splitting hairs here.

But that wasn't all. More links to outside documents appeared in the company rules. In August, Twitter clarified that it would include "indirect threats" under its definition of "hateful conduct." It would also censor people who "incited" harassment, for example by urging their followers to send harassing messages to another user.

At last, in December, the company quit embroidering its rules page with links and simply re-wrote its rules from top to bottom . Now, as Jeong points out, the company no longer promises an uncensored service.

Twitter has discovered what many proponents of democratic society already knew: censorship is not the opposite of free speech. In fact, so-called free speech can actually be used as a weapon to silence the vulnerable and dispossessed. Ironically, to maintain its position as a platform for free discourse, Twitter must censor its users. Like Reddit, this once laissez-faire community is making some basic safety rules. Here's how the company puts it:

We believe in freedom of expression and in speaking truth to power, but that means little as an underlying philosophy if voices are silenced because people are afraid to speak up. In order to ensure that people feel safe expressing diverse opinions and beliefs, we do not tolerate behavior that crosses the line into abuse, including behavior that harasses, intimidates, or uses fear to silence another user’s voice.

Call it what you want, but this is a ban on hate speech. Whether it will actually lead to less harassment on Twitter remains to be seen.