NEW YORK — Reading about the short, troubled life of Freddie Gray — who suffered lead poisoning as a child, was arrested for drug offenses more than a dozen times, and eventually died in police custody nearly two weeks ago in Baltimore — I recalled a description of this world of young men, mostly black, trapped in America’s criminal justice system. It was written by an arch-conservative, who was at the time a prisoner in a Florida jail.

“Many are victims of legal and social injustice, inadequately provided for by the public assistance system, and over-prosecuted and vengefully sentenced,” he wrote. “The failures of American education, social services and justice [are] unaffordable, as well as repulsive. In tens of millions of undervalued human lives ... the United States pays a heavy price for an ethos afflicted by wantonness, waste and official human indifference.”

The author of those words is Conrad Black, once one of the world’s most powerful media barons, who spent more than three years in prison on charges of fraud. Whatever one thinks of Black’s own case, which is complicated and on which he mounts a robust defense, after he became enmeshed in the American judicial system, the Canadian-born (now British) Black studied it intensely and wrote both a book and several essays about it. His lessons are worth taking seriously, since they come from a friend of America and a die-hard conservative at that.

It is well-known by now that with nearly 5 percent of the world’s population, the United States has close to 25 percent of the world’s prisoners and, Black adds, 50 percent of the world’s lawyers. America’s prison population is many, many times higher, per capita, than that of other advanced democracies like Canada, Britain, France and Japan.

Prosecutors win 95 percent of their cases, 90 percent of them without ever having to go to trial, says Black, noting that the overall conviction rate is 60 percent in Canada and around 50 percent in Britain. Are American prosecutors that much better? No, insists Black, it is because of the plea bargain, a system of bullying and intimidation by government lawyers for which they “would be disbarred in most other serious countries, [and which] enables prosecutors to threaten everyone around the target with indictment if they don’t miraculously recall, under careful government coaching, inculpatory evidence.”

In a much-discussed essay in the New York Review of Books, U.S. District Judge Jed Rakoff wrote that because of the plea bargain “the criminal justice system in the United States today bears little relationship to what the Founding Fathers contemplated, what the movies and television portray, or what the average American believes.” There is, more often than not, no “day in court,” no trial, no rights for the accused. The prosecutor almost always gets what he wants. When I served on a grand jury, I quickly realized that it was a rubber stamp for the prosecution.

Black also writes that American prisons are dedicated to punishment with a “primal vindictiveness,” which also ensures that inmates once released are utterly unfit for reintegration into society — virtually guaranteeing that they return to prison. In such European countries as Norway, where the emphasis is almost the opposite — entirely focused on redemption and reintegration — there are dramatically lower rates of recidivism.

In an observation perhaps born of personal experience, Black describes the practice of putting glass barriers between prisoners and their visiting loved ones as “sadistic and dehumanizing.” “It should never be the objective of the state to shatter the family and personal life of prisoners. It is indisputable that normal family, romantic and friendly relations with law-abiding people are a stabilizing influence on people.”

The crime wave of the 1970s scared America. And when scared, Americans often overreact and enact bad legislation. What followed was a spate of laws relating to drugs and crime that has given the police and prosecutors far too much power and the accused too few protections and too little dignity. The zeal to lock up criminals has spawned a vast “prison-industrial complex” that now lobbies aggressively for its own special interests — which of course means more prisoners and, thus, prisons.

The Anglo-American system of law was historically defined by its focus on the rights of the accused, not the powers of the prosecutor. That was how it differed from the vast majority of the world. In describing that system, the great English jurist William Blackstone said, “Better that 10 guilty persons escape than that one innocent suffer.” We have strayed very far from that core conviction in America today.

Fareed Zakaria is a columnist with the Washington Post Writers Group and host of GPS, a public affairs television show on CNN.