No sin in dealing with persons in quid-pro-quid manner

बार कृते प्रतिकृतं कुर्याद् हिन्सने प्रतिहिन्सनम् |
तत्र दोषो न पतति दुष्टे दुष्टं समाचरेत् || – चाणक्य नीति
Meaning : There is no sin in dealing with persons in quid-pro-quid manner . Deal out violence to violent ones and evil to evil character as that is what they deserve.