To friends in the protest movement, Lucy was an eager 20-something who attended their events and sent encouraging e-mails to support their causes. Only one thing seemed strange. At one demonstration, I remember her showing up with a laptop computer and typing away," said Mike Stark, who helped lead the anti-death-penalty march in Baltimore that day. "We all thought that was odd." Not really. The woman was an undercover Maryland State Police trooper who between 2005 and 2007 infiltrated more than two dozen rallies and meetings of nonviolent groups. Maryland officials now concede that, based on information gathered by "Lucy" and others, state police wrongly listed at least 53 Americans as terrorists in a criminal intelligence database -- and shared some information about them with half a dozen state and federal agencies, including the National Security Agency. Among those labeled as terrorists: two Catholic nuns, a former Democratic congressional candidate, a lifelong pacifist and a registered lobbyist. One suspect's file warned that she was "involved in puppet making and allows anarchists to utilize her property for meetings." "There wasn't a scintilla of illegal activity" going on, said David Rocah, an attorney for the American Civil Liberties Union, which filed a lawsuit and in July obtained the first surveillance files. State police have released other heavily redacted documents. Investigators, the files show, targeted groups that advocated against abortion, global warming, nuclear arms, military recruiting in high schools and biodefense research, among other issues.