In Chapter 4 of Just Mercy, what are Bryan Stevenson's views regarding death penalty laws and the changes made by the supreme court in 1989?

Bryan Stevenson’s mission is to challenge racial and economic bias in the U.S. justice system, and his clients are people on death row, people of color who have been marginalized in society, victimized by the system, and convicted of crimes they didn’t commit. Stevenson sees what the public does not see and has little awareness of—a criminal justice system that is badly broken—and he struggles to show mercy to his clients in a system that amounts to nothing short of institutionalized racism. It persecutes people of color and and puts many innocent people to death.
In 1989, the Supreme Court ruled that people who commit crimes at the age sixteen or seventeen are not exempt from the death penalty. Based on Stevenson’s experience, the majority of these young people are poor people and African Americans. In chapter four of Just Mercy, Stevenson witnesses an execution for the first time—the execution of a young client and Vietnam veteran who was innocent of the crime he would die for. What struck me about chapter four was Stevenson’s awareness of the prison authorities. He recognized the hypocrisy of their actions as they offered to give the dying man anything he wanted to make his last day on Earth better. Stevenson told NPR that he will never forget his client telling him that

"more people have said, 'What can I do to help you?' in the last 14 hours of my life than ever did in the first 19 years of my life."

Steven recognized that throughout this young man’s life, people in a position of authority did nothing to make his life better at all.
Stevenson believes that the problem lies in the way society as a whole condones the subjugation of people of color and supports a system of justice that keeps them marginalized and oppressed. Stevenson’s objection to the death penalty comes from his inside knowledge of the personal dynamics that characterize the victim/persecutor relationship. His objection to the death penalty stems from its unfairness, and from a larger sense of historical unfairness—a reality that shook him to the core as he witnessed the death of an innocent victim at the hands of the people responsible for his oppression. In an interview with Oprah, Stevenson claimed that abolishing the death penalty would “liberate us from some of the worst parts of our history." He states that

“You can’t be in counties and communities where people have been lynched and threatened and menaced and terrorized, and then have a person of color taken to death row.”

Seeing the execution of an innocent man made it more crucial for Stevenson to fight the system and to make people aware of the injustice that is inherent in the death penalty and that prevents it from serving justice at all.
https://eji.org/news/bryan-stevenson-tells-oprah-winfrey-why-we-should-abolish-death-penalty/