When may a state deny a defendant the right to a jury trial?

The states should never deny the 6th and 7th amendments of the constitution, guaranteeing a right to a Jury in any controversy amounting to $20 dollars or more. Unfortunately, many states blatantly disregard this provision of the constitution, especially in traffic cases (speeding, lane change violations ect...). Eventually, all articles and amendments of the constitution will be regarded as obsolete by the various branches of government and made void through misinterpretation, leading to some type of 2nd American revolution, or 2nd civil war. Afterwards, there will probably be some type of constitutional inquisition, wherein those congressmen and judges will be tried for treason who deliberately disregarded and undermined the US Constitution.