An action by a federal agency can be constitutionally challenged as being outside of the scope or powers granted to that agency by congress. The constitutional challenge thus would be that the agency is operating outside of the checks and balances system the constitution lays out.
Congress has in the past and can today authorize agencies to do things like collect data on US citizens for national security purposes or public safety purposes.
Congress has in the past and can today authorize agencies to do things like collect data on US citizens for national security purposes or public safety purposes.