Politwoops, a project from the Sunlight Foundation, launched in 2012 with a simple mission: save the deleted tweets that politicians would rather you didn't see. Last night, Twitter shut the project down.

According to a statement released today by the Sunlight Foundation, Twitter decided that Politwoops violated the company's API Terms of Service "on a fundamental level" and decided to have it removed. The Sunlight Foundation says they are unable to appeal the decision, but have decided to "honor Twitter's latest decision," despite working out issues with the company in 2012. According to the statement:

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.