In SWR, "murder" lowers a player's align ever so slightly... By 10, to be exact. However, it doesn't check to ensure that the player's new align is within the given limits... Between -1000 and 1000. Seeing as any other event that modifies align will set them back within those limits, I have to imagine this was a mistake.
In fight.c, in function do_murder(), find:
if( !IS_NPC( victim ) && xIS_SET( ch->act, PLR_NICE ) )
send_to_char( "You feel too nice to do that!\r\n", ch );
ch->alignment -= 10;
Directly below that, add:
ch->alignment = URANGE( -1000, ch->alignment, 1000 );