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?
Juries exist for jury nullification. It’s a check against the problem in law where, when its made easier to convict people who did something bad necessarily makes it easier to convict someone who doesn’t. All laws are like this and it goes both ways. Anti-littering laws could be construed to convict an old person who didn’t notice something slipped out of their pocket. Speeding tickets come with a low fine because everyone speeds, but this limits how much super speeders may be punished.