Until 1986, when they finally let cops carry the speedloaders that they had been screaming for (and many cop carried anyway, against the rules). In 1986, three year veteran Scott Gadell was shot point blank by a suspect with a 9MM. They were involved in a shootout and Gadell had emptied his gun. He was crouched behind a dumpster fumbling to reload his revolver one round at a time (imagine the shaking hands dropping rounds as he fumbled to get them in the gun?). The perp walked right up and shot him in the head.
Look at Amadou Diallo, the man shot at 41 times (19 hits) by cops when he reached for a wallet in a dark hallway. Only two rounds of the 19 that hit him were fatal, but neither instant stoppers. One nicked his aorta. Right after that, we got hollowpoints.
And now that most PD's carry .40 and up,the NYPD is still shooting the 9MM, with no plans to upgrade