Army Legal Services Branch The Army Legal Services Branch ( ALS ) is a branch of the Adjutant - General ' s Corps ( AGC ) in the British Army . Before 1992 , the branch existed as the independent Army Legal Corps ( ALC ) . The ALS consists only of commissioned officer s ( currently about 120 ) , all of them either qualified solicitors , barristers or advocate s . The head of the corps is known as the Director General of Army Legal Services and holds the rank of Major - General . The members of the corps provide legal advice to the Army as an organisation and to individual officers and soldiers . They also provide staff to the Service Prosecuting Authority . History . Many of the functions of the ALS were once carried out by the Judge Advocate General ( JAG ) whose own origins can be traced back to Medieval times . Following World War I , the growing demand for legal services within the army , led in 1923 to the creation of the Military Department of the Office of the Judge Advocate General . The main functions of this office remains at the core of the ALS today . The Directorate of Army Legal Services was formed from the JAG ' s office on 1 October 1948 and would go on to receive full corps status as the Army Legal Corps on 1 November 1978 . It was always the smallest corps in the Army . On 6 April 1992 , the corps became the Army Legal Services Branch of the Adjutant General ' s Corps , but retains a separate identity and its own cap badge . The corps motto was " Justitia in Armis " and the regimental march was " Scales of Justice " , both of which are retained by the Army Legal Services Branch . Structure . The Director General of Army Legal Services is a Major - General . Beneath him there are three Brigadier s . Remaining ALS Officer ranks range from Captain to Colonel . Currently there are : • 10 Colonels • 39 Lieutenant Colonels • 42 Majors • 30 Captains ALS also has a number of Territorial Army officers . In civilian life , many of the TA officers are highly experienced criminal advocates in the Crown Prosecution Service or private practice . Other TA officers are litigation experts , working as partners in firms of solicitors or at the Bar . Areas of expertise . Service Prosecuting Authority . The ALS posts a number of its Officers to the Service Prosecuting Authority ( SPA ) . The most senior military officer in the organisation is a Brigadier of the ALS who is the Deputy Director Service Prosecutions . Officers of the SPA prosecute cases at Court Martial and where appropriate Service Civilian Court . They also act as respondent in the Summary Appeal Court and represent the Crown at the Court Martial Appeal Court . The SPA has its HQ and UK Office at RAF Northolt , in Northwest London . It also maintains an office in Bielefeld , Germany . Advisory Branch . The Advisory Branch of ALS advises the chain of command on a wide variety of administrative , operational and criminal law issues . There are advisory Officers in every major Army HQ around the world . Typically they advise on matters including : whether Commanding Officers should initiate disciplinary procedures for soldiers , Boards of Inquiry , whether administrative action should be taken against those suspected of breaching the Army ' s values and standards , how the Army should deal with grievance s and other employment law related issues , delivering training on disciplinary / administrative processes and on emerging Army policies . Advisory branch Officers often work directly with the Army ’ s most senior commanders . In addition within the Advisory branch there are ALS Officers specialising in particular areas such as specialist employment law , primary and subordinate legislation drafting and the drafting and editing of key documents such as the " Manual of Military Law " and the " Queen ' s Regulations " . Operational Law . When the British Army deploys on operations it takes legal advisors with it . When deployed on operations ALS Officers are often asked to advise on the most sensitive issues , as well as on international law and often on the local law of the country concerned . All army commanders at every level have access to legal advice from ALS Officers and this commitment is increasing all the time both in terms of deployments but also in terms of supporting the Army ' s pre - deployment training requirements . ALS Operational Law branch Officers are also often attached to the operations of NATO and the UN . Also , within the Operational Law is the specialist International Law branch of ALS which is located in MOD and is engaged in higher level issues including advising on the Army ' s interest in the drafting of certain treaties and negotiating and drafting Status of Forces Agreements with other states . Army Legal Assistance . The headquarters of Army Legal Assistance ( ALA ) is presently located at Catterick Barracks , Bielefeld in Germany . This branch provides legal assistance and advice to entitled service personnel and their dependants worldwide . The majority of advice relates to family law , debt and German legal issues . ALA do not deal the Child Support Agency , wills and probate , property law or adoption and fostering . The principle governing the services provided by ALA is that whilst serving overseas servicemen , their dependants and UKBC ' s are not able to obtain from civilian solicitors legal advice and assistance on their personal legal problems . ALA therefore exists to provide this service instead . ALA is a free service , but applicants must fund any court or other fixed costs ( such as divorce fees ) themselves . ALA officers conduct legal clinics in Germany and in operational theatres . Career structure . New ALS officers are commissioned as Captains on a Short Service Commission of four years and 210 days , the first year of which is probationary . This can be extended up to eight years , subject to satisfactory performance . If the commission is confirmed , an officer can apply , subject to having obtained two consecutive annual reports recommending conversion of commission , to convert to an Intermediate Regular Commission ( IRC ) . If an officer obtains an IRC then that commission will allow them to serve up to their eighteen - year point . Once an officer has obtained an IRC then , again subject to obtaining the required recommendations in annual reports , they may apply for conversion to a Regular Commission . If granted , this will allow the officer to serve to the age of 60 or for a total of 34 years from the date of commissioning . Promotion is based on annual reports . Subject to suitability , a Legal Officer may be promoted to the substantive rank of Major after six years ' service , although it is not uncommon for ALS officers to be promoted to Acting Major rank earlier than the six - year point . Once they are a substantive Major , an officer is eligible for promotion to substantive Lieutenant - Colonel after a further six years ' service ( subject to recommendations ) , although again it is not uncommon for ALS officers to be promoted to Acting Lieutenant - Colonel rank earlier .