Many in the music industry paint peer-to-peer file-sharers as devil’s spawn who suck the life blood out of artists. Some P2P proponents have countered that file-sharing has helped encourage the growth of many bands who would have gone unknown in the CD and cassette age. Now comes a new study that each side could point to as support.

ArsTechnica has a great write-up about the new study from researchers at Columbia University who surveyed public behavior and opinion on issues of file-sharing and copyright.

There are lots of good tidbits from the survey, but the one that interested us the most was the data about the music-buying habits of P2P users.

According to the study, the average file-sharer has around 2,000 songs in their music library (which actually seems quite small to us, but we didn’t do the study). Of that number, 760 were purchased legally.

Meanwhile, the average library for a non-P2P user is a bit less than 1,300 songs, 582 of which were bought by the listener.

So you could argue that the P2P user is actually the one supporting the music industry, as he or she has purchased nearly 200 more songs than the person who doesn’t share their files online.

But then again, only around 38% of the P2P user’s library has been purchased legally while 45% of the other library is legitimate.

“Of course, correlation is not causation,” writes ArsTechnica’s Timothy B. Lee. “It’s possible, for example, the most avid music fans are also the most likely to be drawn to peer-to-peer networks. Perhaps without those networks they would have purchased even more music from legitimate services.”

So while this study won’t do much to convince the RIAA that peer-to-peer networks aren’t the worst thing since Crystal Pepsi, it does at least show that those who use P2P also occasionally pay for the songs they want to hear.

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