Checkraise declared out of turn - could I consider this binding?

[DrewOnTilt]

A question out of pure curiosity - Al and other dealers help me out here:

I'm in the 20/40 at the Borg, and seated 2 to my right is a complete maniac.

3 limpers before the maniac, the maniac limps, I raise from the cutoff with K [img]/images/graemlins/diamond.gif[/img]J [img]/images/graemlins/diamond.gif[/img], 3 callers, the maniac limp reraises, and I bust a cap up into that mother [censored].

The flop comes 3 [img]/images/graemlins/club.gif[/img]4 [img]/images/graemlins/club.gif[/img]7 [img]/images/graemlins/spade.gif[/img]

The 3 limpers check, the maniac looks at me and says "I check, and I am going to check-raise you." I check behind.

I was planning to check behind anyway, since I had completely missed the flop, the pot was multiway, and the board was low and highly coordinated. Out of curiosity, could I have held him to this checkraise declaration? He really was going to checkraise, as he had flopped bottom 2 pair [img]/images/graemlins/tongue.gif[/img], but suppose that someone uses this tactic as a means of scaring the preflop aggressor into giving a free card. Would the action be binding?