What do Gaff's origami figures mean?

Chicken:

Deckard is "chicken", he is reluctant to take the job.

Stick man:

Deckard may be getting *too* involved (probably meant in respect to Rachael).

Unicorn:

a) "Gaff was here!" basically, it was a calling card;

b) In the DC, there is an extra layer to it: (See question "Is Deckard A Replicant")

Note: I extracted these pictures from vidcaps in the DVD image library at BladeZone.

Who is this Gaff anyway? What is his function in the LAPD?

We know very little about Gaff. Is he a Blade Runner, like Deckard and Holden? Perhaps, although his physical condition leaves little opportunity to do any "running". Maybe Gaff has some other function within the police department, some sort of supervisor, assigned to keeping an eye on Deckard.

But who really knows what his function is?