Section 2(10) “Board” means a Juvenile Justice Board constituted under section 4
Section 4 of J.J, Act, 2015

(1) Notwithstanding anything contained in the Code of Criminal Procedure, 1973, the State Government shall, constitute for every district, one or more Juvenile Justice Boards for exercising the powers and discharging its functions relating to children in conflict with law under this Act.
(2) A Board shall consist of a Metropolitan Magistrate or a Judicial Magistrate of First Class not being Chief Metropolitan Magistrate or Chief Judicial Magistrate (hereinafter referred to as Principal Magistrate) with at least three years experience and two social workers selected in such manner as may be prescribed, of whom at least one shall be a woman, forming a Bench and every such Bench shall have the powers conferred by the Code of Criminal Procedure, 1973 on a Metropolitan Magistrate or, as the case may be, a Judicial Magistrate of First Class.

Role of JJB as per J.J. Act, 2015

1. Identification of Fit Facility,
2. Identification of Fit Person,
3. Transferring Child to CWC,
4. Receiving a written complaint from the Committee,
5. Functions of Juvenile Justice Board under Section 8 of J.J. Act, 2015:

(a)  Ensuring the informed participation of the child and the parent or guardian, in every step of the process;
(b) Ensuring that the child’s rights are protected throughout the process of apprehending the child, inquiry, aftercare and rehabilitation;
(c) Ensuring availability of legal aid for the child through the legal services institutions;
(d) Wherever necessary the Board shall provide an interpreter or translator, having such qualifications, experience, and on payment of such fees as may be prescribed, to the child if he fails to understand the language used in the proceedings;
(e) Directing the Probation Officer, or in case a Probation Officer is not available to the Child Welfare Officer or a social worker, to undertake a social investigation into the case and submit a social investigation report within a period of fifteen days from the date of first production before the Board to ascertain the circumstances in which the alleged offence was committed;
(f) Adjudicate and dispose of cases of children in conflict with law in accordance with the process of inquiry specified in section 14;
(g) Transferring to the Committee, matters concerning the child alleged to be in conflict with law, stated to be in need of care and protection at any stage, thereby recognizing that a child in conflict with law can also be a child in need of care simultaneously and there is a need for the Committee and the Board to be both involved;
(h) Disposing of the matter and passing a final order that includes an individual care plan for the child’s rehabilitation, including follow up by the Probation Officer or the District Child Protection Unit or a member of a non-governmental organization, as may be required;
(i) Conducting inquiry for declaring fit persons regarding care of children in conflict with law;
(j) Conducting at least one inspection visit every month of residential facilities for children in conflict with law and recommend action for improvement in quality of services to the District Child Protection Unit and the State Government;
(k) Order the police for registration of first information report for offences committed against any child in conflict with law, under this Act or any other law for the time being in force, on a complaint made in this regard;
(l) Order the police for registration of first information report for offences committed against any child in need of care and protection, under this Act or any other law for the time being in force, on a written complaint by a Committee in this regard;
(m) Conducting regular inspection of jails meant for adults to check if any child is lodged in such jails and take immediate measures for transfer of such a child to the observation home; and
(n) Any other function as may be prescribed.

1. Conducting of Inquiries,
2. Submit a quarterly Report to CJM,
3. Removing Recognition of Fit Person / Fit Institutions,
4. Providing for Disclosure of Child’s Details in Press,
5. In case, where any corporal punishment is reported in a institution,
6. Presumption of Determination of Age,
7. Determining the age of Child,
8. Transfer of Child,
9. Granting Leave to a Child,
10. Amend its own orders.