“The common thread” between the three tribunals, he says, “is that these were courts established by treaty or convention and controlled by multiple governments.”

If you add in the fact that the ICTR was “a court for the entire international community, established by statute of the United Nations” and whose budget was agreed annually by the General Assembly, it is clear that political skills need to be woven into the judicial function.

I met with Sir Dennis in October last year to talk about his career, which parallels the growth of jurisprudence, the appellate system and legal education in the Caribbean. He was in England primarily to attend the memorial service in Gray’s Inn of his friend and colleague Karl Hudson-Phillips QC, the former Trinidadian Attorney General and a judge of the then newly-constituted International Criminal Court. He was also here to promote the work of the CCJ whose tenth anniversary will be celebrated this year.

Sir Dennis arrived in Cambridge in 1962 to read law. Although “cricket was my game” it was the English autumn, and so he took up rowing. As he described it, there were several medical students in the boat, and as they had their anatomy lectures in the afternoon, training began at 6 am. “We broke the ice on the river,” something he smiles at now, never having previously lived in a cold climate. When summer came he found himself in a first boat that did so well on the river that cricket was consigned to the weekends. “I played Sunday cricket in the illustrious company” of his contemporary Deryck Murray, the great West Indian cricketer who captained Cambridge at the time.

After being Called by Inner Temple, he went back home to St.Kitts. He began work in Nevis, where his uncle, Cecil Byron, had a law practice and he did some work on Anguilla, where his father was. “I was much more interested in litigation than in the other aspects,” he recalls. In those days the judiciary “was not so well staffed as it is now” so the judges covered several jurisdictions as a result of which “I developed a practice that followed the judge” quite literally around the region. At the age of 38, in 1982, he was appointed a High Court judge of the Eastern Caribbean Supreme Court. By then legal education had been established at the University of the West Indies who produced its first law graduates in 1975. “Many of them have reached the highest level.”

Four years later he presided over the trial of those accused of murdering Maurice Bishop, the Prime Minister of Grenada who was overthrown in October 1983 by his former allies who felt he was betraying his own revolution; the coup leaders were themselves very quickly overthrown by the United States invasion. Karl Hudson-Phillips QC was lead counsel in the trial. The jury returned manslaughter convictions against the soldiers who were obeying orders but murder convictions against the man who admitted killing Bishop and the military and civilian leaders who were not there but who were held responsible for giving the orders.

In 1999 Sir Dennis became Chief Justice of the Eastern Caribbean Supreme Court, whose jurisdiction takes in some nine different states including the British Virgin Islands. It is a court, he explained, without a single Attorney General or Prime Minister and the budget comes from multiple jurisdictions. One of his early achievements was modernising the civil procedure rules in line with what Lord Woolf was doing in England at the time. “Those who have adopted it properly have seen the benefits” he said, and a large percentage of cases are disposed of before trial. He suggested wryly that “excellent courts are those in the continuous process of improvement”. He favours a regional approach. “It is better to have the Caribbean Court of Justice than to have people go to London to litigate at the Privy Council.”

He spent seven years away from the Caribbean during his tenure on the International Criminal Tribunal for Rwanda (ICTR), which was modelled on the court which dealt with the former Yugoslavia. While we spoke, he noted that it is now the 20th anniversary of the genocide and consequently of the establishment of the tribunal. It was decided then that political reconciliation could best be achieved through a judicial process. Looking back “I thought to that extent there were many successes”. There has been discussion on the extent of reconciliation but he pointed to the fact that Rwanda abolished the death penalty. “When you think that the Parliament was dominated by the victims of the genocide”, it took a “spiritual transformation” to do that, and it “fed back into reconciliation”.

The ICTR was based in Arusha, a city in the north of Tanzania, rather than in Rwanda. Arusha had the infrastructure and in 1994 hostilities were still raging in Rwanda so that the security of court personnel could not have been guaranteed at that time. The legacy of the tribunal includes the development of domestic judicial administration. The transfer of cases for trial in domestic jurisdictions contributed to this. It was a judicial process as the transfers were made to courts that were adjudged to apply international standards. The work of the tribunal assisted in developing capacity in Rwanda and eventually cases were transferred to Rwanda for trial there.

Other countries were involved in the transfer process including Norway, which was first required to pass statutes to criminalise the crime of genocide and crimes against humanity. The ICTR is now closed although there is a residual mechanism since some people have not yet been arrested. Altogether Sir Dennis spent seven years with the ICTR, four of them as President.

In 2011 he was appointed President of the Caribbean Court of Justice (CCJ), located in Port-of-Spain and which was inaugurated in 2005. This is a court with two functions. First, it acts as the interpreter of the Treaty of Chaguaramas which was signed in 1973 and established CARICOM, the Caribbean Community and Common Market, which was in turn replaced in 2001 by a single market. The second function is that it is a final court of appeal for the CARICOM states in place of the Privy Council. As late as 2012, English barristers were arguing Trinidad death row cases in front of Supreme Court justices sitting as the Privy Council in Parliament Square.

When I put to Sir Dennis that the Privy Council’s decisions in the death penalty cases were the impetus for forming the court, he replied, “That’s not true at all”. Discussions about the establishment of a regional final court “have been going on for well over 100 years”.

The expansion of the court “completes the circle of independence, and the court has in turn asserted its freedom to depart from British precedents. In 2006, in Attorney-General v Joseph and Boyce, it was faced with the issue of whether the Barbados Privy Council was entitled to confirm a decision not to recommend commutation of the death penalty before the defendant’s petition to the Inter-American Commission for Human Rights had been resolved. The judgment stated that “we do not agree with the reasoning” by which the British Privy Council had reached its decision in a comparable, previous case, but “We have achieved the same result in this case but by a different route.” The court reflects an area with differences in nationality, ethnicity and religion, but “There are too many interests in the Caribbean to support a quota system for choosing judges”, he said. Judges are selected by the completely independent Regional Legal and Judicial Services Commission whose members are chosen by regional institutions including the Bar Associations and law faculties and the legal council. Most of the countries have common law jurisdictions but Guyana uses Roman-Dutch law and St Lucia uses the Code de Quebec of 1861. The court uses e-filing and videoconferencing but it can also travel. “We have developed a Caribbean jurisprudence,” he said, “linked to international principles.”

It has been over 50 years since Sir Dennis studied law in a cold climate. Since then he and the Caribbean courts over which he has presided have taken their places on a world stage.