the guy was riding a scooter - in the general scheme of things no real harm done. it's not as if he had just knifed someone or set off a bomb or beat up his wife. so OP didn't know who was in the right or wrong.
i also believe the police officer tried to detain the person and they simply didn't want to be detained.
he was then making the judgement call that the police officer was in the right even though he had no idea what was going on, could be an illegal detainment. police officers are human. humans can make mistakes and you do have corrupt coppers out there too. without any facts he shouldn't be intervening when the guy has caused no harm to anyone bar the person detaining them and in that instance has used just enough force to stop them detaining him.
all he had to do was let him go. then chase it up later when he had his fellow officers with him or send out an APB and request back up. he had no idea who was in the right or wrong and it's being automatically assumed the officer was in the right with no facts.
i would like to see what OP had done if there was no police officer. but a civilian trying to stop the guy with the scooter. would he have helped? i seriously doubt it. which again shows just because they are a police officer they must be in the right and cannot possibly be wrong.
i had a police officer who i had asked for help state that x was y. I then read out the law to them stating x was x and they then tried to use an excerpt to say they had reasonable cause. i then had to read out to said police officer reasonable cause in such circumstances is for as an example emergency services cutting someone out a car to save their life. therefore said person couldn't get emergency services done for vandalism for damaging the car as they had reasonable cause to damage the car; to save the persons life who was trapped in said car. but if some yob decides smash your car up to get into it isn't excluded under reasonable cause like emergency services are. officer refused to listen when pointed out they were wrong on both accounts until i asked to speak to their boss. who fully agreed with me.
so you can't assume they are correct and know the law.
Conscript again beat me to it but...
Ah, finally something semi-sensible as opposed to a troll/wind up...
Well no, he clearly didn't want to have a chat, slap on the wrist, be detained or arrested at all as he tried to do a runner!?
The OP did have a little more than an idea of what was going on, as he clearly saw him on an illegal vehicle and that was what the guy was being stopped about!?
...The guy was only giving sweets out to kids outside a school...he was only walking the streets at 2am with a knife in his hand...they had only scaled the fence of the Nuclear power station...he/she was only doing 45mph in a 30 mph zone etc. Where do you draw the line and actually stop someone that's either doing something illegal or in all likelihood, will lead to something illegal happening shortly. I would hope any copper worth his or her salt will try and prevent crime and the likelihood of it happening in the not too distant future.
If a copper in this country asks you to step out of your car (if that's what your inferring to in the latter part of your post) then whether you know why they're asking you to do so or not, it's probably wise you do as they ask. You can have a quick safe chat about whatever the issue may or may not be and be on your way...or you can do a runner like the guy in the OP and likely be in more trouble later on...or be all bolshy about it and stay in your car - at which point you may have your car inspected for the slightest infraction. It's your call at the end of the day, but I'm pretty sure there's only one sensible option. All this 'fight the system' went out in the 80s I'm sorry to say...
*Just to quantify things a little from my distant past here. I and many others were involved in the Toxteth riots of 1981. No one in Liverpool liked the cops back then due to them completely abusing their powers. There were plenty of reasons behind the riots but one favourite of the cops back then was to pick up small groups of youths (having a ciggie on the corner of a street, going to a youth club or simply doing absolutely nothing as there was nothing to do etc) and give them a kicking in the back of vans and then kick them out miles from anywhere. As a consequence many of us both initiated and got into fights with them - small ones, big ones and the ones where you knew that if you got grabbed by them you could expect a long term in hospital (if you were lucky). Sometimes we'd single out one or two of them if the chance was right too - it was nasty for a time back them. Welp...since then both I and the cops in this country have mellowed quite a bit I find lol. Since then I've probably had a couple of hundred talks/chats about very minor issues with cops across the country and not once was I detained at all and I merrily went on my way.
