Couple of thoughts. Notice the “gentle policing”, no handcuffs so he was able to gesticulate during his performance. The cops must have been laughing their asses off when he was “arguing his case”. They probably wanted to club him to stop the “singing”.
Cops probably have at least one unsolved murder they can pin on him, after all, he just confessed!!
That jumped out at me right away. First time I’ve ever seen someone arrested that was not transported in handcuffs.