A former Los Angeles police sergeant charged in a federal wiretapping case testified Friday that he ran names through criminal databases on behalf of an indicted private eye Anthony Pellicano but didn't accept bribes for the work.

Defendant Mark Arneson testified that he knew that accessing people's private information was improper but thought it would bring only minor punishment such as a reprimand.

Arneson is accused of taking bribes from Pellicano in excess of $180,000 as part of a scheme that used clandestine tactics to dig up dirt to aid clients in legal and other disputes.

Arneson says the money he received from Pellicano was for off-duty security work that included escorting stars to award shows and conducting surveillance.

Earlier, an FBI agent testified Friday that he was unable to decrypt some audio files seized during raids on the offices of Pellicano.

FBI agent Donald Schmidt was the only witness called by Pellicano, who is acting as his own attorney. Pellicano reserved the right to testify on his own behalf later in the trial.

Lawyers for four other defendants were set to begin presenting their cases.

Pellicano questioned Schmidt, an Internet technology specialist, for about an hour.

The agent testified that he was instructed to look for calls that had been wiretapped among the recordings found during raids that began in November 2002.

He said he unable to listen to some of the encrypted calls.

"Did you find any evidence of wiretaps?" Pellicano asked.

"I found what sounded like telephone recordings," Schmidt replied.

'Do you know what a wiretap is?" Pellicano asked.

"I was instructed to look for audio files," Schmidt said.

During the trial, prosecutors played at least six recordings of calls between Pellicano and clients but only one tape they characterized as a wiretap.

Pellicano's wife Kat Pellicano and his two teenage daughters were in court while he presented his defense. He winked in their direction while he questioned Schmidt.

Pellicano and four co-defendants have pleaded not guilty to charges involving the use of clandestine tactics to dig up dirt to aid clients in legal and other disputes.

A total of 28 charges were dropped at the prosecution's request Thursday.