They should focus less on retribution and more on rehabilitation.
Most people want to make sure convicted criminals have it as bad as humanly possible; that is the WRONG approach. Not only is it inhumane, but it also drastically increases recidivism.
Some really insidious laws that need to go away are Felony Disenfranchisement (laws that prevent prisoners and ex-convicts from voting -
a practice rooted in racism which still keeps an millions of reformed citizens out of the voting booth and therefore prevents politicians from caring about them), three strike laws (where crimes receive harsher punishments the more they are enforced - good in theory but in practice often leading to people being sentenced to life imprisonment for stealing a single slice of pizza), Strict Liability (a law by which someone is guilty of a crime regardless of if they willingly or even intended to commit a crime - if a 17 year old sleeps with an adult by lying about age and showing a fake ID, the adult still gets charged with statutory rape), and Zero Tolerance (a law and school policy by which everyone who commits a specific crime receives a specific punishment regardless of circumstances, duress and insanity be dammed - this leads to crack dealers spending more time in prison than child molesters).
A big problem is that too many criminal laws are passed not by rational adults analyzing what is best for society as a whole, but rather by over-emotional politicians making knee-jerk decisions and temper-tantrums. That’s the only way you can explain things like 12 year olds being sentenced to life imprisonment without parole (something the Supreme Court actually had to address and pass laws against).
But an even bigger problem is how cruel society can be towards criminals. Women getting raped at college is an outrage, but young prisoners getting raped by their cellmates while guards look the other way is treated at best as a natural part of the punishment and at worst as something they deserve. Television shows and movies make jokes about it all the time, and often these jokes amount to little more than “Haha! His cellmate is sodomizing him against his will! It’s funny because he’s a prisoner so he had it coming!”.
That’s why prisons can get away with a lot of horrible abuse: turning a blind eye when prisoners get raped by their cellmates (ignoring complaints and continuing to put them in the same cell together), abandoning prisoners to drown in sewage during a Hurricane, making them live in tents where they are exposed to the elements, putting them in solitary confinement for decades on end, putting them on feeding tubes when they protest for basic human rights, refuse to pay for medication that prevents them from dying an excruciating death, and charging them fees they can’t afford when they try to sue for human rights.
Prisoners aren’t animals and they aren’t demons from Hell; most are regular people who made a mistake or never had good role models to teach them right from wrong. If you vote to make life harder for prisoners “because they deserve it”, then don’t complain when there’s a tax raise to pay for the massive prison system in the US.