The RIPA gives too many government departments unnecessary powers to pry into the lives of citizens . And there are plenty of examples of the misuse of the act.
A society where everyone is being spied on all the time is not one which will ever be happy with itself. Britain is already a surveilance society, and this act plays a large part in enabling this.
The police, Customs, and others already had adequate powers, there is no case for DEFRA for example to be given powers to act like MI5