Who was the leader of the consumer movement in US?

I would say that Ralph Nader was the person most responsible that jump-started the consumer movement, begining in the 1960's. He was largely responsible for having GM stop producing the corvair. He proved it was very unsafe to drive. He testified before congressional hearings numerous times,

wrote many books, and has lectured all over the United States for consumer protections and safeguards! The only major blemish to his reputation, was in 2000, when he ran as a 3rd party candidate against George Bush and Al Gore.

He took just enought votes away from Gore, to give the election to Bush. The rest, they say, is history!