'There shall be no Alsatia here’ is a traditional assertion of judicial jurisdiction over the objections of the Crown. The erudite Lord Justice Sedley was rather fond of the phrase. Historically, it alludes to the legal sanctuary derived from the presence of Whitefriars monastery, south of Fleet Street in London.

Thus, the fate of Alsatia (from which the king’s writ was resisted for nearly two centuries after the monasteries went) provides an appropriate image of the onward march of judicial accountability. In turn, this illustrates one of the successes – albeit faltering and yet imperfect – of the Human Rights Act.

The importance of the recent decisions of the European Court of Human Rights in Al-Skeini and Al-Jedda can hardly be overstated. The issue in the first case was whether south-eastern Iraq was ‘within the jurisdiction of the UK at the relevant period’. The court found that it was, declaring: ‘Following the removal from power of the Ba’ath regime and until the accession of the interim government, the United Kingdom… assumed in Iraq the exercise of some of the public powers normally to be exercised by a sovereign government. In particular… authority and responsibility for the maintenance of security.’

The second case decided that the UK could not evade the application of the convention by arguing that it was acting under a UN resolution.

The question of the potential extra-territorial application of the convention has some history. The application of the European convention to the UK’s then colonies was a major bone of contention in the 1950s. A number of derogations were made and some attention given to tricky issues arising from the then widespread practice within the British empire of collective punishment. Government officials decided in 1959 that silence was best because public acknowledgement ‘would call attention to the existence of collective punishment not only in Nyasaland but in certain other territories, and might give rise to serious embarrassment’.

It took 60 years but eventually the European court caught up with the UK in the way that the Colonial Office feared. Where the UK effectively assumes the role of government overseas, the convention applies as it does at home.

The UK must, therefore, apply the convention within the territories for which it exercises governmental responsibility. This is a major step forward but, for all that, a little limited. Liability in Iraq would have lasted for around a year and probably never arose in Afghanistan.

The court’s decisions require a reappraisal of existing caselaw. Nevertheless, even our Supreme Court decided that the convention covered Baha Mousa, killed by British soldiers while they detained him in Basra. That decision, in turn, triggered an inquiry chaired by Sir William Gage and recently dramatised by the Guardian’s Richard Norton-Taylor for the Tricycle Theatre in London. Sir William has announced he will publish his report on 8 September. It will be interesting to see if he reaches the same conclusions as the play does about the misinformation provided by former minister Adam Ingram concerning International Red Cross complaints.

The convention has helped to place the military’s treatment of detainees under the microscope: it provides a set of standards by which they can be judged. The deaths of Baha Mousa and Hamid al-Sweady have given rise to inquiries required by article 2 of the convention. In parallel, David Cameron announced in August an inquiry chaired by Sir Peter Gibson – with former Law Society chief executive Janet Paraskeva on an advisory panel – to investigate more general allegations of UK complicity with the US and others in relation to article 3’s prohibition of torture and ill-treatment.

The judicial committee of the House of Lords deserves praise for its clarification that the common law prohibited evidence obtained by torture (A v Secretary of State (no 2), [2005] UKHL 71), a strong line which helped to underline the importance of the UK’s respect of article 3.

The courts have also asserted their right to decide on what should be published, not the government’s. Alas, the credibility of the Gibson inquiry has been somewhat tarnished by the withdrawal of Justice, other human rights organisations and solicitors for the detainees because of its insufficient independence – particularly in relation to decisions on publication. In 1967, Lord Justice Salmon, chair of a Royal Commission on Public Inquiries, cogently expressed the problem of too much secrecy: ‘The public may be left with the feeling that the inquiry, if behind closed doors, is no more than what is sometimes referred to as "the usual whitewashing exercise".’

The courts have declined to inquire into the justification for the Iraq war, though the Brown government stepped in with an inquiry led by Lord Hutton. This did not get very far: outside their own courts, judges can look like rabbits paralysed in the political headlights. They are more at ease with individual cases in a court setting. Thus, the mother of Private Jason Smith made some advances in obtaining an inquiry into her son’s death in Iraq from heatstroke.

A more recent case accepted that there might be liability under the convention in relation to negligence over equipment, even though the court upheld the general principle of ‘combat immunity’ (Smith v MoD [2011] EWHC 2008 (Admin)).

Thus, we have slow - but measurable - attrition of the no-go area or Alsatia that has hitherto covered military action. Prime ministers have long found judges useful to front public inquiries: this has rarely been a complete success for either judge or politician.

However, hesitantly and slowly, the Human Rights Act is advancing judicial supervision within the courts themselves. One of the last frontiers is being crossed. About time.

Roger Smith is director of the law reform and human rights organisation Justice