The phrase "to reform the criminal" means helping a person who has committed a crime to change their behavior and become a better, law-abiding individual. Full definition
This is all good even if it is not the ambitious reforms our criminal justice system needs. (canadianlawyermag.com)
The director of acclaimed sports doc Hoop Dreams spends a year with Chicago's «Violence Interrupters», a group of reformed criminals who try to defuse situations before they escalate. (theguardian.com)
As you already know, Lynch and the PBA accused Big Apple Mayor Bill de Blasio and advocates for reforming criminal justice systems nationwide of having «blood» on their «hands» this past weekend after tragic murders of police officers Wenjian Liu and Rafael Ramos by Ismaaiyl Brinsley (who had come to town after a rampage that included critically wounding his ex-girlfriend). (californiapolicycenter.org)