UK EV drivers using medical cannabis should be aware of the ‘in charge’ rules...

https://ace-wiki.win/index.php/Do_Police_Accept_My_Prescription_at_the_Roadside_or_Do_They_Still_Arrest_You%3F

UK EV drivers using medical cannabis should be aware of the ‘in charge’ rules that apply when parked and charging. Even with a prescription, the legal THC limit of 2 micrograms per litre of blood applies