Stat services that rule on fairness of trades?

Two members of our 12-team league now serve as co-commissioners.  Our league 
would prefer to have a neutral third party rule on the fairness of trades, 
even if we have to pay for it.

Does any stat service provide that service?  I know that ESPN does it, but 
they have a 10-team limit.

Does any other service rule on trades?

- Joe Rossmeissl
Madison, WI