Ok some facts.
They cant pull you over for nothing. They cant search the van without good reason, eg, they have to have evidence of Drug Use (like the smell of cannabis) to search the vehicle under the Misuse of Drugs Act, or it stinks of alchohol to search it for drink, and breathalyse you.
You are not obliged to get out your car and sit in his car. You are not obliged to produce any documents, and most Road Traffic solicitors will advise you NOT to produce your licence at the road side.
You are entitled to record the conversation with the copper, whether he likes it or not, If he trys to prevent you, you point out you are recording for evidence purposes, and any attempt to stop you or delete the photos/ recording is destruction of evidence and illegal.
The general rule is say as little as possible to the police. You MUST realise the truth of the caution 'Anything you say may be used as evidence against you' - and nothing you say will be used in your defence. Every single sentence the copper says to you is designed to get you to incriminate yourself, and the more you say, even if you are perfectly innocent, the more can be taken out of context and used against you. They are NOT obliged to tell YOU anything at all, especially things that might indicate your innocence.
Take the question 'Do you know what the speed limit along here is'. This is a loaded question, like many question they ask you. there is NO answer you can give to this question that does not incriminate you. e.g "Yes it 40 MPH" - "Oh so you knew you were speeding" , or "No" - " Oh so you wernt paying due care and attention to the road markings" If at all possible, DO NOT give the police any ammunition, however trivial, say as little as possible. You are obliged ONLY to stop, and identify yourself.
If you are arrested, the officer MUST say to you after he cautions you 'Do you understand'. The Only thing you you say, and the thing you MUST say is 'NO, i do not understand the meaning and consequence of the words just spoken to me", and the copper IS legally obliged to record you rely. If you are asked to sit in the back of the police car, decline. If you are arrested and forced into the back, say nothing from that point on, and sign nothing till you have gotten legal advice.
Furthermore, when in the police car, yo are entitled to see a copy of PACE (Police and Criminal Evidence Act). They are supposed to have a copy in the car, but they never do, so everything stops then till they radio back to base and another copper drives out with it, and they then have to sit and wait till you read it, all 1700 pages. Another point is you are entitled to have a friend sit in the back with you and take notes about the conversation. If you cant record it on a mobile, at least do that. They wont like it, but they cant stop you doing it.
Realise that 80% of all convictions in court are because a copper stops someone, and in the subsequent conversation, the victim says enough to incriminate himself, even for things he was never stopped for.
The last time i was stopped, it was for creeping through a traffic light in heavy traffic, it went red when i was halfway across. Immediately a copper switches lane and chases me. The first thing i observed was a) hes alone and b) theres no video in his car. He walks over, and my son immediately starts recording the conversation using his Iphone. The copper asks me why i think he stopped me,, i said i had no idea. he said i went through the red light, i said i was sure it was amber. he said it was red, i repeated i was sure it was amber. He then clocks hes being recorded, and visibly reacts. He again accuses me of going on red, i said well we'll have to agree to disagree. He then says its lucky, he hasnt got his ticket book on him, or hed give me a ticket, and dont do it again., and leaves.
In fact he didnt have a leg to stand on. Every copper has a ticket book in the car, the truth was he was alone (and therefore didnt have another copper to lie and back up his story), he had no in car video, and there was no CCTV, so he had no video proof, but i had a recording of the conversation, so i can prove if he lies, so had it gone to court it would have been my word and my video against his word alone, and it would have got thrown out. So the ****** about having no ticket book was just to save face and exit with dignity from the hole he dug himself.
Copper always travel in twos so they can back up each others story in court. Take speed cameras, hand held. There not supposed to just gun anything that goes past in hope its speeding, the one with the gun has to 'form an opinion' you are speeding and then a second copper also has to 'form an opinion' that you are speeding, then they can gun you. OFC what happens in practice is they just gun everything randomly to see what they can catch and then collude and lie through there teeth in court about 'forming an opinion' first.
Take time to watch THIS:
WHY YOU SHOULD NEVER TALK TO THIS POLICE
Its american, but most of it applies here as well, its well worth watching.