The request had a twist: Instead of asking to eavesdrop on the contents of the e-mail messages, which would require some evidence of wrongdoing, prosecutors instead requested the identities of the correspondents. Also included in the request was header information like date and time and Internet address--but not subject lines.
Reason number 342 to not renew the Patriot Act. It seems that all those wonderful "protections" that we're told are in there--aren't. Read the entire article and be infuriated.