A man who federal authorities said engaged in "overt sexual activity" on a flight to Raleigh actually was just not feeling well, his attorney said Tuesday.

Raleigh lawyer Deb Newton said her client, Carl Warren Persing, laid his head on his girlfriend's lap because he was drowsy. The gesture was misinterpreted by a flight attendant, who then humiliated and harassed the couple, Newton said.

Persing and Dawn Elizabeth Sewell, both of Lakewood, Calif., are charged in federal court with interfering with flight crew members stemming from their Sept. 15 Southwest Airlines flight from Los Angeles with a stop in Phoenix.

Raw Data: U.S. v. Persing, Sewell (FindLaw pdf)

Law enforcement officials were waiting for the couple when they arrived at Raleigh-Durham International Airport. The couple spent three days in jail, Newton said.

When a flight attendant asked the couple to stop their public displays of affection, they initially obeyed but resumed the behavior shortly thereafter, court documents state.

"The one witness I've talked to and the defendant dispute almost everything in the government's affidavit as to what happened on that airplane," Newton said.

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She said she will ask that the charges be dismissed. Persing's trial was delayed until February.

Newton also said Persing suffers from a chronic disease that requires medication that makes him drowsy, dizzy and irritable. She declined to identify the disease to protect her client's privacy.

A message left by The Associated Press for Sewell's attorney was not immediately returned.