“I am deeply concerned at the disproportionate number of young African Americans who die in encounters with police officers, as well as the disproportionate number of African Americans in US prisons and the disproportionate number of African Americans on Death Row,” said UN High Commissioner for Human Rights, Zeid Ra'ad Al Hussein, in a statement issued by his office in Geneva this morning.

“It is clear that, at least among some sectors of the population, there is a deep and festering lack of confidence in the fairness of the justice and law enforcement systems,” Mr. Zeid continued. “I urge the US authorities to conduct in-depth examinations into how race-related issues are affecting law enforcement and the administration of justice, both at the federal and state levels.”

Michael Brown was shot by a white police officer in the US town of Ferguson, in Missouri on 9 August, sparking protests around the country and enflaming the debate surrounding the treatment of African-American men by US law enforcement.

Amid reports that many of the protests in and around Ferguson had turned violent, UN Secretary-General Ban Ki-moon called for calm and restraint, appealing to all those demonstrating against the Grand Jury's verdict “to make their voices heard peacefully and to refrain from violence.” Speaking through his spokesperson, Mr. Ban urged local authorities “to protect the rights of peaceful demonstration and freedom of expression.

“He echoes the appeal made by Michael Brown's parents to turn this difficult time into 'positive change,'” the spokesperson, Stéphane Dujarric, said, adding that Mr. Ban's thoughts were “first and foremost” with Michael Brown's family and with the entire Ferguson community.

The High Commissioner explained that without knowing the specific details of the evidence laid before the state of Missouri Grand Jury, he remained unable to comment on whether or not the verdict itself conformed to international law. However, he said, continuing reports of deadly encounters between police officers and members of the African-American community had repeatedly prompted concerns among respected national bodies and by UN bodies monitoring the implementation of international human rights treaties.

Mr. Zeid noted that just two weeks ago, Mr. Brown's parents had addressed the UN Committee against Torture, which is currently reviewing the US application of its obligations under the relevant Convention.

The Grand Jury's decision last night to not charge the officer, Darren Wilson, comes just three days after another African-American, Tamir Rice, was shot dead by police in Cleveland, in the State of Ohio, because he was holding a non-lethal replica gun. Tamir Rice was 12 years-old.

Mr. Zeid noted that Tamir Rice's killing not only reiterated the racial disparity in deaths at the hands of US police officers but also placed the issue of gun-related deaths in the US back into focus.

“In many countries, where real guns are not so easily available, police tend to view boys playing with replica guns as precisely what they are, rather than as a danger to be neutralized,” he stated.

Pointing to Article 9 of the UN's Basic Principles on the Use of Force and Firearms by Law Enforcement Officials, Mr. Zeid confirmed that law enforcement officials were called upon to “not use firearms against persons except in self-defence or defence of others against the imminent threat of death or serious injury.”

“In any event, intentional lethal use of firearms may only be made when strictly unavoidable in order to protect life,” the High Commissioner concluded.