There is an ancient Sloka recited by king Marutta, quite of a piece with Brihaspati's view, O king, about the duty of kings.
मरुत्तेन हि राज्ञा वै गीत: श्लोकः पुरातनः। राजाधिकारे राजेन्द्र बृहस्पतिमते पुरा॥