i think that's where the whole new testament comes in with jesus  "fulfilling the old testament laws" -  to point out that as humans ,we are flawed,  that NOBODY does just righteous. but if we truly could follow in the footsteps of only righteousness... judges, cops - the whole legal systems wouldn't be needed - nobody would do bad. - hence no one would have to be  it the position of judging or controlling another person. .it's a tough concept to explain - as are most bible ones.. but that's my understanding of the stuff - i've pondered all that too. and you did it out there as a question..
 being an observer in court and seeing innocent people found guilty  and thinking the judge is (hopefully) fair and thinks it's the right decision. i would never want to be in that position of the big decider or guilt and punishment. with exceptions regarding my prison/island that i bring up on occasion. yeah i fall short all the time..