The House Freedom Caucus announced Thursday it will oppose reauthorizing the FISA Amendments Act, the legal basis for U.S. surveillance programs, without “substantial” reforms to the law.

Section 702 of that law has come under fire recently after revelations that this provision was used to capture communications of President Trump and his transition team as it had conversations with foreign officials. Under the law, this kind of incidental collection of information from U.S. citizens occurs, but U.S. citizens caught up in that surveillance are usually masked, unless intelligence officials decide there is a good reason to unmask that person.