This is not unusual behaviour by a CPD officer. What is unusual is that the video tape did not just disappear as usually happens to evidence of LE misconduct. I suspect it was recorded off site.
That's actually not a bad idea, with the dropped price and easy availablity of web-enabled cams. Have your security cameras be recording offsite, or several places offsite, in case arson destroys the place itself, or someone wants to hush it all up. The recording will still exist and be safe.