A U.S. attorney has charged Bryan Wagner, an independent investigator who worked for Hewlett-Packard while the company tried to find the source of board leaks, with aggravated identity theft and conspiracy.

Wagner is one of a group of people working for HP charged with crimes following revelations that HP investigators used questionable tactics to obtain the personal information of HP board members, reporters and reporters' family members during HP operations in 2005 and 2006. In October, former HP Chairman Patricia Dunn, former HP ethics counsel Kevin Hunsaker and three investigators including Wagner were charged by the office of California Attorney General Bill Lockyer with fraudulent wire communications, wrongful use of computer data, identity theft and conspiracy.

Kevin Ryan, the U.S. attorney for the Northern District of California, filed the new charges against Wagner Wednesday. Wagner faces up to five years in prison and a $250,000 fine for the conspiracy charge, and two years in prison and a $250,000 fine for the charge of aggravated identity theft and aiding and abetting.

Ryan charged Wagner with helping to obtain the names, addresses, Social Security numbers, telephone call logs, telephone billing records and other information of the HP board members and reporters. Wagner worked for Action Search Group, a subcontractor to Security Outsourcing Solutions, the company HP hired to help with security investigations, according to court papers filed by Ryan.

Wagner used a reporter's Social Security number to establish an online account and obtain the reporter's phone records, according to the court records.