GTA Vice City - Gang Members Won't Shoot You Hex Trick:

Go to the "\data" folder in your Vice City directory
Open "pedstats.dat" with any text editor (such as Notepad)
Look at where it says "STAT_GANG[#] (going 1 through 7)
Under column "D" where it has 20, change that to 80
Do it for the gangs you want to have respect with (they won't shoot you).
Here's an example of how it looks:

A B C D E F G H I J
STAT_GANG1 17.0 7.5 80 65 10 40 1.0 1.0 6
STAT_GANG2 17.0 7.5 80 65 10 40 1.0 1.0 14
STAT_GANG3 17.0 7.5 80 65 10 40 1.0 1.0 6
STAT_GANG4 17.0 7.5 80 65 10 40 1.0 1.0 6
STAT_GANG5 17.0 7.5 80 65 10 40 1.0 1.0 14
STAT_GANG6 17.0 7.5 80 65 10 40 1.0 1.0 6
STAT_GANG7 17.0 7.5 80 65 10 40 1.0 1.0 6