I doubt the outcome would be any different in terms of actually punishment, but cake fines are considered bullying and were on their way out almost a decade ago when i went..
In the old barely-post-PACE days when I joined you've be called into the area commanders office (back then a full chief supernintendo) and shouted at until you've were quivering. Then, if you were lucky, you'd be facing a £100 fine to be donated to a charity of his choice.
If you were unlucky it would be a full misconduct job (not a 'disciplinary' as the idiot media report it) where you could be in serious sheet, but that would take something very serious to trigger and would be done with fairly swiftly.
I think back then that car would have been the bollarding, the £100 charity donation, and a 6 month to a year hold on any career plans you might have. A punishment meaningful enough to make you think twice next time, that didn't keep an experienced bobby out of circulation for 2 years on restricted duties while civilians who had never walked a beat investigated it, and which was over and done with then and there.
Today it'd be a full investigation that might take a year or more, a hearing, the public invited to watch, and an enormous waste of everyone's precious time for likely a good bollarding from the area commander, a written warning, and 6 month to a year hold on any career plans you might have...