related to that testing. The sum shall not exceed the reasonable cost of providing the services for which the sum is intended.

On November 1 of each year, the treasurer of each county shall determine those moneys in the special account that were not expended during the preceding fiscal year, and shall transfer those moneys into the general fund of the county. The board of supervisors may, by resolution, assign the treasurer’s duty to determine the amount of money that was not expended to the auditor or another county officer. The county may retain an amount of that money equal to its administrative cost incurred pursuant to this section, and shall distribute the remainder pursuant to Section 1463. If the account becomes exhausted, the public entity ordering a test performed pursuant to this subdivision shall bear the costs of the test.

authorize an additional penalty upon each defendant convicted of a violation of Section 23152 or 23153 of the Vehicle Code, of an amount equal to the cost of testing for alcohol content, less the fifty dollars ($50) deposited as provided in subdivision (a). The additional penalty authorized by this subdivision shall be imposed only in those instances where the defendant has the ability to pay, but in no case shall the defendant be ordered to pay a penalty in excess of fifty dollars ($50). The penalty authorized shall be deposited directly with the county, or city or special district within the county, that performed the test, in the special account described in subdivision (a), and shall not be the basis for an additional assessment pursuant to Section 1464, or Chapter 12 (commencing with Section 76010) of Title 8 of the Government Code.

For purposes of this subdivision, “ability to pay” means the overall capability of the defendant to pay the additional penalty

authorized by this subdivision, taking into consideration all of the following: