The wartime captain in the Scots Guards, who went on to play an integral role in the legal profession, died peacefully at his home in Perthshire on Sunday, surrounded by his family. He was 94.
Sir William led the excoriating report into the Metropolitan Police’s actions after the racially motivated killing of the black teenager in 1993.
Upon its publication in 1999, the 350 page-long report signalled one of the most significant moments in the modern history of criminal justice.
It concluded that the force’s investigation had been "marred by a combination of professional incompetence, institutional racism and a failure of leadership". Specific officers in the Metropolitan Police were named and the entire force was criticised.
In the aftermath, Sir William was subjected to denigration professionally and personally. But some 67 of the report’s recommendations led directly to specific changes in practice or the law within two years of its publication. They included the creation of the Independent Police Complaints Commission, with the power to appoint its own investigators.
In an interview two years ago, Sir William downplayed his role in the sweeping changes his report brought about.
“I'm pleased we achieved what we did, which was to give a strong push to people in the right direction,” he said. “We could do no more than that, of course. Because I couldn't work miracles about making police behave better or improving the relationships between black and white people.
"There's obviously more to be done, but my feeling is that great steps have been taken in the right direction."
As a retired High Court judge, Sir William had already enjoyed a long and distinguished career at the Bar before helming the inquiry.
He also played an active role as the head of his clan, serving as its chief since 1969. Known affectionately as ‘Cluny’, he hardly ever missed one of its annual gatherings in Newtonmore.
Among those to pay tribute was the Clan Macpherson Association, which said it was fortunate to have benefited from “his guidance, support, and leadership” for a half century, describing him as “a man who left his mark on those he met.”
Hashi Mohamed, the barrister and broadcaster, said: “For me, Sir William’s passing is a seminal moment. He definitely had a legacy which improved race relations in this country, which was immensely important.”
John Swinney, the deputy first minister, said he was “very sorry” to hear of the death of Sir William, who was one of his constituents.
Praising the impact of his report into the Metropolitan Police, he added: “The challenge, rigour, and humanity of his report was a product of who he was. He did much good locally in Blairgowrie.”
Pete Wishart, the SNP MP for Perth and North Perthshire, tweeted: “So sad to hear of the death of Sir William Macpherson. Sir William led the Macpherson report into the death of Stephen Lawrence that transformed issues around racism in the met police force. In Blairgowrie he’ll just be remembered for his immense contribution to the community.”