AUDIT would also make it easier to track law enforcement surveillance at a larger scale. It would use multi-party computation (where different groups work on the same project) across higher and lower courts to disclose large volumes of info without asking institutions to share info between each other. You could get transparency into data requests without having to talk to multiple services.

The approach is still a proof of concept at this stage, although CSAIL is considering the possibility of working with federal judges to craft a real-world version. The team would also like to refine the system to handle more sophisticated requests. However, the greater challenge may be getting support for the idea in the first place. Law enforcement is sometimes less than fond of transparency, and it may be reluctant to adopt a public ledger even if data showed up well after an investigation was over.