The explosive idea of forcing Internet providers to record their customers' online activities for future police access is gaining ground in state capitols and in Washington, D.C.... Mandatory data retention requirements worry privacy advocates because they permit police to obtain records of e-mail chatter, Web browsing or chat-room activity that normally would have been discarded after a few months. And some proposals would require providers to retain data that ordinarily never would have been kept at all.... Jim Harper, director of information policy studies at the free-market Cato Institute, was the member of the Homeland Security's Data Privacy and Integrity...