Near the end of three hours of testimony ranging from matter-of-fact to jocular to nostalgic about his youthful enjoyment of music, defendant Joel Tenenbaum admitted liability for downloading and distributing the 30 copyrighted songs at issue in a federal copyright infringement trial in Boston.

The admission prompted the lawyers representing the music industry to ask U.S. District Judge Nancy Gertner to issue a directed verdict — a ruling in favor of the plaintiffs after they finish presenting their case — said Cara Duckworth, a spokeswoman for the Recording Industry Association of America.