Did police belief in discredited lie detector test cause them to let Chandra Levy's killer go free?

Arrest Near in Killing of Chandra Levy, Authorities Say
New York Times
By IAN URBINA
February 21, 2009

Police officials here are close to making an arrest in the killing of Chandra Levy, the former federal government intern whose disappearance in 2001 ended Gary A. Condit’s Congressional career after his relationship with her was revealed, several law enforcement officials familiar with the investigation said on Saturday.

Law enforcement officials, who spoke on the condition of anonymity because charges had not been filed, identified the suspect as Ingmar Guandique, 27, a Salvadoran immigrant who has previously denied any involvement in Ms. Levy’s disappearance and killing.

Ms. Levy’s killing is one of Washington’s most sensational unsolved crimes and has brought intense pressure on the Police Department. Ms. Levy disappeared on May 1, 2001, and more than a year passed before her body was found in Rock Creek Park in Washington.

Mr. Guandique pleaded guilty to assault in September 2001 in two cases involving attacks on women in the park in May and July 2001. He is now serving a 10-year sentence at a federal prison in Adelanto, Calif., and is eligible for parole in 2011.

The police recently submitted new evidence to the United States attorney’s office after an inmate serving time with Mr. Guandique contacted them, law enforcement officials said. The inmate said Mr. Guandique told him he had killed Ms. Levy, the sources said.

In the initial investigation, Mr. Guandique told the police that he had seen Ms. Levy in the park, but that he had not harmed her. The police called Mr. Guandique a “person of interest,” but said he had passed a polygraph test...