> Yet the conviction rate in England was 84 % in magistrates courts (misdemeanors and low level felonies) and 78 % in crown courts (more serious crimes) which is not that different.

The conviction rate can't really tell you anything because prosecutors will calibrate to bring cases they think they can win in a given system. Systems willing to convict more innocent people will have similar conviction rates but more innocent defendants.

> A good judge wouldn’t do that.

What about a human judge?

> Also by and large random people are relatively dumb and biased. Why exactly are they less likely to convict an innocent person?

Because you have to convince all twelve of them.