Why doesn't the federal government do something about the national problem of mentally unstable cops?

Denver police officer charged with DUI hired despite prior conviction
Denver Post
A Denver police officer charged last week with drunken driving was hired despite a prior DUI conviction because there was no rule against his employment at that time. But in 2000, just a year after Jessie Anthony Espinoza II became a patrolman, the ...
Off-duty officer charged with DWI and leaving scene after crash
TimesLedger
FOREST HILLS — An off-duty New York Police Department officer was arrested within the 112th Precinct and charged with driving while intoxicated, police said. According to the NYPD, 27-year-old Wesam Isaac was arrested Jan. 2 around 1:45 a.m. and ...
Columbia, SC Police Officer Charged with DUI
A police officer in Columbia, SC faces DUI charges after driving erratically while at the scene of a call. He will be fired, and faces criminal charges.
stromlaw.com/.../columbia-sc-police-officer-charged-with-dui/