The biggest argument I hear from American libs in favor of the concept is that the court system does not have enough resources to handle every case going to trial. I am absolutely dumbfounded liberals somehow aren't be able to see what a massive self-own that is. Maybe don't fucking arrest so many people that you literally have the largest prison population on Earth?

A guilty plea is supposed to be an admission of guilt, the purpose of which being to save the court time if the defendant wishes to come clean and accept the consequences. So how does it make even the smallest modicum of sense to take someone who does not wish to plead guilty and threaten them with a much harsher sentence if they don't?

Absent a trial, the prosecution doesn't even know yet with confidence whether or not the defendant committed the crime. It's plausible, extremely likely even, that the person they are threatening is actually innocent. Now the guilty plea is no longer an actual admission of guilt, but a means of self preservation if the defendant isn't hopeful about the odds of clearing their name.