In South Africa there are no juries, and the democracy is deemed fairly good, albeit rotten with corruption (but that's another story). The judiciary is fairly independent so far, and criminal cases are solely tried by a professional judge.
A lot of public law jurisdictions don’t have jury trials, just a judge who decides the facts based on the constitution and the case presented by the prosecutor. Finland, for example.
Could you name a few? I'm genuinely ignorant on how most of the world handles criminal affairs - do they just have the judge rule on the matter?