The department oversees the maintenance of law and order, prevention and control of crime, prosecution of criminals besides dealing with Fire Services and Prisons Administration.

[7] The Home Department is responsible for maintenance of internal security and enforcement of law and order in the state of Bihar.

[8] The department answers the questions in the Legislative Assembly/Legislative Council, addresses the issues related to the affairs of the State Human Rights Commission, and National Human Rights Commission.

It also coordinates police and law and order related matters with the Ministry of Home Affairs, Government of India.

The department ensures the security arrangements of citizens, VIPs and state guests and also is the cadre controlling authority of Indian Police Service, and Bihar Police Service.