It's a Vietnamese torture gimmick. See, It's the tourniquet principle. The quarter means a more gradual death.
8 seconds sound clip from the Kojak - Season 1, Ep. 5 - Girl in the River movie soundboard.
You can hear this line at 00:04:07 in the DVD version of the movie.
Quote context
[...]
- For reasons we can only guess at, Excalibur has signed off for two years.
- A quarter put into the stocking with which he garroted his victims.
- Does that ring anybody's chimes?
- Crocker?
- Interesting. Very interesting.
- You know this creep's makeup.
- Oh, and concentrate on Vietnam returnees.
- Uh, that house where Edna Bell was staying you speak to the owners yet?
[...]