(a) Penalty.--If arbitration or a claim with the Board of Claims or a court of competent jurisdiction is commenced to recover payment due under this subchapter and it is determined that the government agency, contractor or subcontractor has failed to comply with the payment terms of this subchapter, the arbitrator, the Board of Claims or the court may award, in addition to all other damages due, a penalty equal to 1% per month of the amount that was withheld in bad faith. An amount shall be deemed to have been withheld in bad faith to the extent that the withholding was arbitrary or vexatious. An amount shall not be deemed to have been withheld in bad faith to the extent it was withheld pursuant to section 3934 (relating to withholding of payment for good faith claims).

(b) Attorney fees.--Notwithstanding any agreement to the contrary, the prevailing party in any proceeding to recover any payment under this subchapter may be awarded a reasonable attorney fee in an amount to be determined by the Board of Claims, court or arbitrator, together with expenses, if it is determined that the government agency, contractor or subcontractor acted in bad faith. An amount shall be deemed to have been withheld in bad faith to the extent that the withholding was arbitrary or vexatious.