SCOTTSDALE, Ariz. -- Newly obtained documents reveal a former Scottsdale police officer may have illegally strip searched as many as 20 Valley women during his two years on the force.

• Watch: Strip Search Tactics By Ex-Officer Questioned

Chong Kim resigned in June 2008 amid allegations he threatened to arrest and jail a 19-year-old woman unless she stripped and showed him her private areas.

When that complaint was made public, Scottsdale police admitted they had received a similar complaint against Kim in 2007. Internal Affairs investigated that complaint and exonerated Kim based on a lack of evidence.

In a summary of the internal affairs report from 2008, investigators noted that Kim admitted lying to them when first confronted with the accusations.

Kim then told investigators he coerced both of his accusers to show him their breasts and undergarments or face going to jail, the report said.

Kim also said that he searched females inappropriately an estimated 15 to 20 times during his approximately two years as a police officer, the report said.

In one instance, Kim admitted to using his tactics on a 16-year-old girl involved in a family fight, according to the report.

In another situation, Kim described how he pulled over a couple in a car, the report said. Kim told investigators he put the driver's wife in the back of his patrol car for the sole purpose of getting her to expose herself to him, the report said.

Scottsdale police said they looked into Kim's confessions but were unable to locate any additional victims.

A police spokesman said the department also investigated possible criminal charges against Kim, but determine he did not violate any state laws.

"Clearly this was an officer who was going way beyond his job description," said Ulises Ferragut, a defense attorney who has been involved in similar cases.

The Maricopa County Attorney's office confirmed a case against Kim was never sent to their office. Public records obtained Tuesday show Kim was placed on the Brady List -- a list of officers with credibility issues.

Scottsdale police confirmed they turned the investigation over to the FBI. The U. S. Department of Justice's civil rights division confirmed it has an open criminal investigation into this case.

Last week, the Scottsdale city council approved a $315,000 payout to settle a civil lawsuit filed by the 19-year-old victim from June 2008.