[Hitek]

Your code is a little bit incorrect!
I'd better use

Code:

public IsACop(killerid)
{
        if(GetPlayerSkin(killerid) == 280 || GetPlayerSkin(killerid) == 281 || GetPlayerSkin(killerid) == 282 || GetPlayerSkin(killerid) == 283 || GetPlayerSkin(killerid) == 284 || GetPlayerSkin(killerid) == 285 || GetPlayerSkin(killerid) == 286 || GetPlayerSkin(killerid) == 287 || GetPlayerSkin(killerid) == 288)
        {
                return 1;
        }
        else
        {
                return 0;
        }
}

Check your other scripts and PLUGINS also streamer you use and if your pawn include matches with plugin ver