Judge Advocate General

Who is the Judge Advocate General?

The current Judge Advocate General (JAG) is His Honour Judge Alan Large (pictured).

The best-known part of the Service Justice System (SJS) is the Court Martial.

This is a standing court (equivalent to the Crown Court) created by the Armed Forces Act 2006 which hears criminal and disciplinary cases involving Service personnel in the Royal Navy, the Army and the Royal Air Force, and civilians subject to Service discipline, for serious offences (or where the defendant chooses not to be dealt with by the Commanding Officer).

The judges who preside in the Court Martial are called Judge Advocates. This is a historic title; they are judges alone and have no advocacy role. Judge Advocates also preside over the Summary Appeal Court (equivalent to a Circuit Judge hearing appeals from the Magistrates’ Court), and the Service Civilian Court (a special court to hear cases overseas involving civilians who are subject to Service discipline). All Judge Advocates are members of the independent judiciary, appointed on merit by the independent Judicial Appointments Commission, and all are civilians, although some have served in the Armed Forces.

The Judge Advocate General (JAG) is the senior Judge Advocate and the judicial head of the Service Courts. This is an entirely standalone role meaning that the JAG is not supervised by any other judge and he does not come under the authority of any Presiding Judge nor the Lord Chief Justice. The Service Justice System as a whole comes under the responsibility of the Ministry of Defence. The JAG is appointed by His Majesty the King by means of Letters Patent, on the recommendation of the Lord Chancellor. The JAG is not a General of the Army; the word “general” signifies broad oversight, as in Secretary-General, Attorney-General, etc.

As judicial head of the Service Courts, the JAG has an important role in working with central government to ensure that the system operates effectively. This involves liaison with the Ministry of Defence, the Service Prosecuting Authority, the Military Court Service, the Services and other agencies both directly and through the small Office of the Judge Advocate General (OJAG) which operates as a Private Office. The JAG’s Letters Patent give authority over all Service personnel in relation to the business of the courts and provide the authority to issue sentencing guidelines and practice directions for the Service Courts. Within the Service Courts, the JAG also specifies which judge is to sit on each case.

The JAG also represents the Service justice system internationally. As the UK’s system is well-respected globally, the JAG is frequently contacted by other jurisdictions to give guidance and to influence change in other jurisdictions. The JAG is particularly well-placed to assist Commonwealth nations.

The duties of the JAG include the following:

  • To act as the Presiding Judge in the Services’ criminal jurisdiction and leader of its judges, thereby supervising the jurisdiction
  • To provide advice to all stakeholders in the SJS on practices and procedures, developments and reforms
  • Where appropriate, to monitor the workings of the Service Courts and to advise on its efficiency and effectiveness
  • To issue practice directions for the Service Courts
  • To issue sentencing guidelines for the Service Courts for disciplinary offences and to give guidance on Service reasons for departing from Sentencing Council Guidelines where appropriate (as permitted by Armed Forces Act 2006 s259(2)
  • To issue procedural guidance for the Service Courts
  • To be an observer at the Services Justice Executive Group and Service Justice Board
  • To chair the Service Courts Rules Review Committee
  • To specify and deploy judges to conduct specific trials in the Court Martial in the UK or abroad
  • To provide judges to sit in the Summary Appeal Court and Service Civilian Court, and to rule upon applications for detention in custody and for search and arrest warrants
  • To sit as a trial judge
  • To refer to the Court Martial Appeal Court cases involving a point of law of exceptional importance
  • To maintain records.


The Annual Report of the Office of the Judge Advocate General 2021-22 (PDF)
17 January 2023

Practice Memoranda

The Judge Advocate General has issued the following Practice Memoranda:

Practice Notes

The Judge Advocate General has issued the following Practice Notes:

Sentencing Guidance

The Judge Advocate General has issued guidance for sentencing in the Court Martial:

Guide to Procedure and Guidance for Board Members

The Judge Advocate General and the Military Court Service has issued the following guidance:

Contact details – The Office of the Judge Advocate General (OJAG)

The Office of the Judge Advocate General
9th Floor, Thomas More Building,
The Royal Courts of Justice,
The Strand, London. WC2A 2LL

Day to day administration is carried out by Jennifer Jarvis
For policy issues please contact Alex Clark, the JAG’s Private Secretary
Email address: OJAG@Judiciary.uk