Fighting a drug driving charge

I was caught with a very low level in my blood after being targeted and swabbed constantly by the police.I’m fortunate enough to have the money spare to get myself a good solicitor – they have picked many holes in their case and procedures and it’s looking like I’m either going to be charged with a lesser offence, or none at all. I have pleaded not guilty but the case will not be until late next year, so I will keep you updated.I’ll spare the details until after my case. but what I found most shocking about getting the papers from cps, was that the arresting officer has said in his statement that he swabbed me because of a ‘plastic bag of herbal cannabis’ found in my car. There was never anything found on me/in the car and I’ve never been caught with anything previously. Don’t trust the police!Edit: thanks for the advice everyone is giving, but I’ll leave that to my solicitor via /r/uktrees