Rome - An electronic bug was found in the offices of the Italian judges due to hear a final appeal this month by former premier Silvio Berlusconi against a tax fraud conviction, news reports said on Friday.
An employee of the Court of Cassation discovered a device used to record or intercept conversations and alerted police on Thursday afternoon, the Rome-based Il Tempo newspaper said.
The bug, which was removed by police, did not have any batteries, the daily said.
A spokesperson for the court was not immediately available for comment.
The Court of Cassation is due on 30 July to consider whether to uphold a four-year jail term - with a three-year discount - and a five-year ban on public office for Italy's conservative leader, who was tried over offshore deals by his family's media firm, Mediaset.
Judges might take weeks to deliver their ruling. If the conviction is upheld, Berlusconi would be forced to step down from Parliament, and if that happens, his backers have threatened to bring down the grand coalition government of Prime Minister Enrico Letta.