All nations within the Anglosphere (US, UK, CA, AU & NZ) have JD imposed towards citizens. I know that the US & Canada both inherited that from Britain, which explains why they have it. However, should it be entirely only the judge making the conviction (some countries operate on a lay-judge system meaning juries aren’t used, such as Finland or Japan for example) rather than leaving that decision up to jurors?
Yeah that’s the opposite side of the jury nullification coin. There’s better examples than weed. In a lot of cases cops plant evidence of crimes and there isn’t much that the law would have to say in court, but the jury might suss it out.