Though the Fourteenth Amendment guarantees equal protection under the law, American history shows this is not always easy to do.
Consumer and other public interest lobbies, according to Jeffrey Berry (pp.334), are organizations that seek “a collective good, the achievement of which will not selectively and materially benefit the membership or activists of the organization.”
The variety of public interest groups include groups seeking to protect those who cannot defend or speak for themselves such as children or the mentally ill.