You can check ABA rates at Ritz-Carlton hotels by inserting the corporate code ABA in the corporate rate field at their website online booking engine. Or you can call Ritz. Many Ritz-Carltons not listed on the sheet have an ABA corporate rate.

And if you are a lawyer, you should be a member of the ABA - for a lot of other reasons which are beyond the scope of this thread and a travel BB. The hotel rate program is not a reason to join, but it is a nice perk that members get. It is certainly not the reason (or even a reason) to join.