Luigi Mangione prosecutors say they didn't eavesdrop on call with his attorney

NEW YORK -- Federal prosecutors said no one from the state or federal government eavesdropped on a jailhouse phone conversation between accused UnitedHealthcare CEO killer Luigi Mangione and his lawyer.

Defense attorney Karen Friedman Agnifilo claimed at a court appearance last week that prosecutors at the Manhattan District Attorney's office had been "eavesdropping" on a call after federal prosecutors provided them with a recording.

Judge Margaret Garnett asked for an explanation, which federal prosecutors provided in a court filing.

"To be sure, no one at [the Manhattan DA's office] or the Government 'eavesdropped' on the defendant on a live basis," prosecutors said in the filing Tuesday. "Rather, consistent with well-known practice in federal and state jails, many of the defendants' calls are recorded with notice of the recording provided to him and the person on the other side of any calls."

Prosecutors said a paralegal inadvertently listened to a call between Mangione and Agnifilo but stopped as soon as it became clear it was a lawyer on the other end of the line.

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Prosecutors reminded Agnifilo there are ways for attorneys to bypass recorded lines when setting up calls with incarcerated clients and told the judge no further action was needed.

Mangione is accused of gunning down UnitedHealthcare CEO Brian Thompson outside a Midtown Manhattan hotel as Thompson headed to an investors conference on Dec. 4. Mangione was arrested in Altoona, Pennsylvania, five days after the assassination-style killing.

Mangione has pleaded not guilty to state and federal charges. The federal charge of murder through the use of a firearm would make him eligible for the death penalty if convicted.