stumped.....12a task orientated groups improperly taking power, sir? (7,7) - - - - - - - - - - - i - s
28a how teams changed, up to a point (8) - - - - w - - -
8d discriminating, again imposed legal punishment (7) r - - - - - -
18d police with weapon that was used to punish mutineers (7) - -r - a - -
I know this is a cryptic crossword, but I'm going gaga with it, any help very welcome.....