[BluffTHIS!]

There are checks and balances in both the American and British systems, appeals and pardons. But the best one is the jury system. Sure it's not perfect, and innocent people have most definitely been convicted and even hanged. Hoever, unless evidence can be shown to the contrary, I would assume that upwards of 98% of people who are convicted are in fact guilty, and thus would maintain that there is no reason not to have strong disincentives for the guilty to go to trial just so that 2% or less who might actually be innocent receive lighter sentences.