Apple is on trial this month, having to defend against allegations that it broke antitrust laws and stifled competition in the music players and downloads businesses with its iPod and iTunes practices. The Wall Street Journal reports that attorneys for the plaintiffs on Wednesday told jurors that between 2007 and 2009 Apple regularly deleted music from iPods that stored downloads from other services, without telling users what was going on.

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“You guys decided to give them the worst possible experience and blow up [a user’s music library],” attorney Patrick Coughlin said in court.

What used to happen is that iTunes would detect music downloaded on other services when a user tried to sync an iPod to his or her iTunes library, and would display an error message telling the user to restore the device to factory settings. Once the restore was complete, the music would disappear from that device.

According to Coughlin, Apple intentionally hid these details from users.

Apple security director Augustin Farrugia said that Apple didn’t want to explain things in more detail as the company doesn’t “need to give users too much information.” “We don’t want to confuse users,” he said.

Furthermore, he said that Apple was paranoid about security, which is why it defended its iPod and iTunes ecosystem in such a way. “Someone is breaking into our house,” Steve Jobs wrote about music pirates in an email to Apple’s Eddy Cue that’s listed as an exhibit in the trial.