One of the screenshots for the game mentions that killing pigeons doesn't affect your score.
Well, it may not affect it, but the game does keep count of how many birds you've killed, and it tells you the final tally when you complete the game! Add
Did You Know?
November 17, 2006 - #10 Worst Game on a "Top Ten Best and Worst Games of All Time" list (Some reasons given were the non-stop gratuitous swearing, bad voice impersonations of Will Smith and Martin Lawrence, shooting watermelons raising your bad cop meter, bad targeting and more glitches than a beta test.)