Catherine Crump is a civil liberties lawyer whose work focuses on combating government surveillance and protecting the free speech rights of political protesters. She has filed cases challenging the NSA and the Department of Homeland Security. Crump is an assistant professor at Berkeley Law School; previously she was an attorney for ACLU for nine years.

In her writing for the ACLU, Crump warns against the dangers of national mass surveillance technology, which can all too easily end up as tools for local police forces. She writes, "Not only our country as a whole, but also the police, will be better off in the long run if we have an open debate about what today’s technology can do, versus what it should do."