A diagnosis of advanced-stage cancer tends to inspire reflection on what matters in one's life. In the case of former Hennepin County Attorney Tom Johnson, it also has inspired a desire to urge all men past age 50 to get an annual PSA test.

I promised him I'd pass that along.

Johnson's reflections on a lifetime in and around Minnesota's criminal-justice system are what brought me to his Minneapolis law office, where he remains on hand most days. I'd heard that the mild-mannered 70-year-old did something unexpected last month as he accepted the county attorney's office award for lifetime achievement in community leadership. He confessed to a leadership failure.

"Reflecting on my career, I realize that there have been times when an opportunity to lead presented itself, but I didn't step up," he said that day. "I backed away, or I went at it halfheartedly."

As county attorney from 1979 to 1991, "I observed up close the problems and challenges facing the African-American community. On a number of occasions I thought about plunging in and figuring out what could be done to change a particular situation. Too often, I didn't, at least not with the vigor I typically try to bring to resolving an issue."

He told himself then that the black community's problems were theirs to solve. "But the difference between a valid reason and mere rationalization can be razor-thin. And I see clearly now that my decision may very well have been different if my heart had been filled with more compassion and my conscience more alert. I simply needed to ask if there were ways I could help."

More compassion. More attentive consciences. More willingness to forge relationships across racial lines. Those are the qualities Johnson says Minnesotans need to muster to narrow what he called a "deplorable racial disparity in our justice system." As of Jan. 1, people of color comprised 17 percent of the state's population and 47 percent of its prison population, according to the state Department of Corrections.

Minnesota now has an urgent need to give all of its sons and daughters an equal opportunity to succeed. If that does not happen, Johnson warns, "we'll go to hell in a handbasket in this state in the next couple of decades." Minnesota's next generations of adults will be much more racially diverse than previous ones. This state's best economic asset, its well-educated workforce, will melt away unless Minnesota gets better at preparing all of its citizens for productive lives.

That's the conclusion Johnson says he distilled from his own regrets ("I stopped door-knocking in north Minneapolis — there weren't enough votes there") and his takeaway from nine years heading the Council on Crime and Justice, from 1999 to 2008. On his watch, the council made a chilling projection. The Minnesota prison population would double by 2030, a major study predicted in 2007, fueled by a doubling of the number of black Minnesotans arrested and a 25 percent increase in total arrests. That forecast is proving depressingly prescient.

I asked Johnson for specific policy recommendations for reversing those trends. He had quite a few. But his central message at the awards ceremony and in the days since has been aimed not at elected officials, but at his fellow citizens. All Minnesotans need to work harder at getting to know people from races and cultures other than their own, he said.

"There's so much room for individuals to play a role in fixing this problem. We need to do find a way to do the things across racial and cultural lines that we would do if that barrier were not there." Things like socializing after work. Asking how things are going and really listening to the answer. Helping a young person make the connections that lead to a first job.

If Minnesota's white majority develops deeper compassion and a keener conscience about racial injustice, he predicts, policy changes will follow. Johnson's wish list includes these items:

• Rethink Minnesota's drug policy, which disproportionately lands the poor and people of color in jail or prison. "Drug use in Minnesota is very comparable across racial lines, but you wouldn't know that by looking at who's in prison," Johnson said.

• Rethink policing practices that crack down on minor offenses in poor neighborhoods that would be overlooked elsewhere. "Too much policing gives the appearance of addressing crime problems, rather than going to the core of the problem," he said.

• Rethink the bail system. "The greatest predictor of one's ultimate sentence is whether or not you're out on bail," he said, with defendants too poor to afford bail also more likely to get a stiffer sentence.

• Rethink voter eligibility laws. Keeping felons disenfranchised after their release from prison sends the counterproductive message that "you're not a full citizen." A change in this state law is on the docket for consideration by the 2016 Legislature.

That sounds like a multiyear agenda. But maybe because he's a fellow whose personal horizon has been shortened, Johnson points out that American attitudes sometimes change quickly. Over the span of only a few years, Americans have changed their minds about same-sex marriage, domestic abuse, drinking and driving, tobacco use and more, he noted.

Minnesota's attitudes about race can be next, he said: "My optimism says we can do it. My pragmatism says we must do it."

Another fellow who talks about the power of compassion and conscience, Pope Francis, is quickly changing perceptions about the message of the Roman Catholic Church. Johnson is a Francis fan. He and his wife, Victoria, were Sen. Amy Klobuchar's guests when the pope visited Washington in September.

He says he came home from that experience convinced that "more people need to be leaders in the call to step out of our embrace of indifference." Even, evidently, people who are battling cancer.

Lori Sturdevant, an editorial writer and columnist, is at lsturdevant@startribune.com.