A former New Canaan Nature Center employee who supervised Timothy J. Yancey violated the center's policy when he failed to report Yancey's on-campus possession of child pornography.

Yancey, 57, of Milford, was arrested last month for allegedly possessing 70 images of child pornography. He was charged with first-degree child pornography possession and is being held on $250,000 bond.

The arrest stemmed from a complaint that the former Nature Center maintenance worker had child pornography on his assigned IBM desktop work computer, as first reported by the New Canaan News.

In April 2009, Yancey's supervisor told a fellow employee that he saw Yancey looking at child porn at his desk on three occasions, the affidavit said. The supervisor told the employee that he cut a slat in the window blinds between his and Yancey's desks to spy on Yancey, but did not confront Yancey until after the third incident, according to the affidavit.

A Nature Center policy requires that any employee who witnesses a felony being committed on the property must report it to his or her supervisor immediately, according to Executive Director Laura Heckman.

"There is a policy and the individual had undergone training ... [and] he didn't follow the policy," Heckman said.

The supervisor later denied ever catching Yancey with child pornography, according to the affidavit.

The supervisor, who is no longer employed at the Nature Center, was never reprimanded for violating the policy because he left the center's employ before Heckman learned that he had previous knowledge of Yancey's behavior, Heckman said.

"He was no longer employed here, so it was a moot point," Heckman said.

Yancey, who worked at the Nature Center for more than eight months, first came under suspicion at the center in the winter of 2009. Heckman confronted him about spending an abnormal amount of time on his computer, the affidavit said.

"Yancey told Heckman he took initiative and was conducting an inventory using the computer," the document said. "Heckman asked Yancey if she could see what he had done so far and Yancey was not able to provide her with an inventory."

"I had no reason to think he was doing anything unlawful," Heckman said of the incident.

Yancey was suspended with pay when federal agents seized his computer on April 20, 2009, and terminated two days later, according to the affidavit.

He is being held at Bridgeport Correctional Facility on $250,000 bail, and is scheduled to return to court on April 14.