Police said the mid-morning collision happened in wet conditions at the intersection of Joondalup Drive and Wanneroo Road on May 21.
No one was seriously injured but it is police protocol for internal investigators to review crashes involving police cars.
Driver Training Unit officer in charge Dave Hornsby said the training vehicle, which was carrying four officers, was travelling east on Joondalup Drive when it collided with a white 4WD heading north on Wanneroo Road.
The driver of the 4WD was treated for minor injuries at Joondalup Health Campus.
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READ NOWSen Sgt Hornsby said it was an unfortunate situation.
‘The (police) driver was a bit shaken up, as was the instructor. They pretty much collided at 90 degrees,’ he said.
A police vehicle was involved in a crash at the same intersection in 2011. In that collision, the patrol car had run a red light while travelling on Wanneroo Road to an urgent incident.