The Boston University graduate student charged with illegally downloading songs online took the stand Thursday and, under questioning from a recording industry attorney, admitted downloading and sharing hundreds of songs.

In only the second Recording Industry Association of America (RIAA) music lawsuit to go to trial, the student, Joel Tenenbaum, didn't deny that he downloaded music. His lawyer has argued that he was just a kid doing when kids do on the Internet.

If the jury rules against Tenenbaum, he could face penalties of up to $4.5 million. Participants in the trial in a Boston courtroom have said they expect testimony in the case to conclude before the week is over.

Specifically, Tenenbaum is accused of downloading 30 songs, although in his courtroom appearance Thursday he admitted to downloading hundreds of songs. Among the songs he downloaded and shared over Kazaa's file-sharing software are songs by Nirvana, Green Day, and the Smashing Pumpkins. The recording companies that leveled charges against Tenenbaum are subsidiaries of Sony, Universal Music Group, and Warner Music Group.

The recording industry has already racked up a big victory against a file-sharing individual accused of illegally downloading music. Earlier this year, a jury in Minnesota ruled that a working mother is liable for $1.92 million in penalties for copyright infringement. In that case, and in Tenenbaum's, the recording industry has argued that "real people" have been damaged by what it terms the illegal downloading of copyrighted music.

The recording industry initially brought legal action against thousands of individuals it charged with illegally downloading music and Tenenbaum's case is among those. However, the industry has recently worked with Internet service providers to stop the illegal sharing of music.

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