Apple has been engaged in a lawsuit this week over what some deemed “anticompetitive” measures put into place in the iPod several years ago. Those measures essentially prevented users from playing back any music from third-party stores. Apple, for its part, has owned up to those actions, saying it did so to protect the user experience and the device from possible malicious files.

Today a former engineer who worked on iTunes at the time testified that he was part of a team responsible for ensuring that music from all competing stores was blocked from working on the iPod. He held to Apple’s claim that it was done for security and user experience reasons.

The iTunes engineer was the final witness to be called in the trial, following several others including Steve Jobs himself through a videotaped deposition that was played earlier this week. At this point, the outcome is in the jury’s hands. Deliberations are expected to start next week.