In 2012, Twitter made the decision to allow Sunlight to curate the deleted tweets from lawmakers and those seeking elected office. Last night all that changed.

When we launched Politwoops three years ago, our goal was to create accountability and a public record for the messages elected officials and candidates for president, vice president, Congress and governor published on social media, particularly those public statements they delete.

What our elected officials say is a matter of public record, and Twitter is an increasingly important part of how our elected officials communicate with the public. This kind of dialogue between we the people and those who represent us is an important part of any democratic system. And even in the case of deleted tweets, it’s also a public part — these tweets are live and viewable by anyone on Twitter.com and other platforms for at least some amount of time.

Unfortunately, Twitter’s decision to pull the plug on Politwoops is a reminder of how the Internet isn’t truly a public square. Our shared conversations are increasingly taking place in privately owned and managed walled gardens, which means that the politics that occur in such conversations are subject to private rules. (In this case, Twitter’s terms of service for usage of its API.)

Politwoops was created because public communications from public officials should be available to anyone who wants to see them. The site isn’t just about blunders, but rather revealing a more intimate perspective on our politicians and how they communicate with their constituents. It has created a unique lens to reveal how the messages from elected officials can change without notice or explanation — because Politwoops did not allow for such reversal of messaging to quietly be swept under the rug.

Days after Politwoops launched in 2012, Twitter contacted the Sunlight Foundation and told us, “Your service violates our API Terms of Service on a fundamental level.” We explained the goals of the project and agreed to create a human curation workflow to ensure that the site screened out corrected low-value tweets like typos, links and Twitter handles. We implemented this layer of journalistic judgment with blessings from Twitter and the site continued.

We are truly mystified as to what prompted the change of heart, and it’s deeply disappointing to see Twitter kill a project they had supported since 2012. It is also disturbing to us that our feed was cut almost three weeks ago and our only direct communication came from Twitter last night, when we were told that their decision was not something that we could appeal, and, most surprisingly, they were not interested in reviewing any of the email conversation from 2012. Clearly, something changed — and we’re not likely to ever know what it was.

In a statement released to Gawker, Twitter said that “Honoring the expectation of user privacy for all accounts is a priority for us, whether the user is anonymous or a member of Congress.” We will honor Twitter’s latest decision, but it stands at odds with a fundamental understanding of our democracy. A member of Congress does not and should not have the same expectation of privacy as a private citizen. Power can only be accountable with a generous application of transparency.

Despite this news, Sunlight will continue to work to open up more data and help lead the movement to make our government and our politics more open and accountable. To those who were fans of Politwoops, we share your sadness at the demise of this tool. To those who have spoken out over the past few days, we thank you for your support and your passion. And to our friends at Twitter, we remain enthusiastic about the potential it has for supporting a healthy civic discourse — even if we clearly have some work left to do to determine how our expectations for public discourse will play out in a privately managed space.