Where a rate of interest greater than the maximum permitted by law is contracted for, reserved or received, directly or indirectly, all payments of money or property made on account of such interest, or as inducements to contract for more than the maximum permitted by law, whether made in advance or not, shall be deemed payments made on account of the principal. In an action brought to recover the amount of the obligation the court shall give judgment for no greater amount than the balance determined to be due upon the principal, without interest, after deducting such payments.
A.R.S. § 44-1203