Hard day at work

The trope of chalk outlines around bodies was never a real thing that cops did.
It was invented by Hollywood in the 50s to suggest the presence of a corpse or murder without showing a corpse onscreen, which would have caused the show to be classified out of its desired classification or be censored.
Cops never did that because it would contaminate the scene and wasn't actually useful to them

people painting lines on football fields may have a word
- Those are just large fields of murdered line people. Tragic we play games on those crime scenes.
  
  pours Gatorade out for the fallen victims

Dude doesn't have a chalk roller? He's pretty shit at his job if he doesn't know how to use chalk on grass like a sports arena would.
- Bucket of white paint .... just throw a few gallons over the body .... instant outline
  
  That's so stupid. Just gently tip a bucket around the edges of the body, you'll waste a lot less paint.
- I'm a Doctor not a Stadium Employee!

Fun fact: it's not chalk (at least in Spain). I had to clean these marks, not from a corpse (the guy didn't died) but from the blood splashes and bullet holes, and I had to use solvent to take them out, the industrial cleaning products did nothing.