Their project was inspired by the Norwegian approach to incarceration that believes rehabilitation in humane prisons surrounded by nature leads to successful reintegration into society, even for those who have committed terrible crimes.
Norway is a long, narrow country in northern Europe, running 1,100 miles from north to south. It has set up small prisons across the country, which allows people to serve their sentences close to home, said Kristian Mjland, a Norwegian associate professor of sociology at the University of Agder in Kristiansand.
The entire country has about 3,000 people in prison, he said, putting Norway's per-capita incarceration rate at roughly one-tenth that of the United States.
Norway has some of the world's lowest levels of recidivism. Government statistics give the proportion of people reconvicted within two years of release in 2020 as 16%, with the figure falling each year. Meanwhile, a U.S. Department of Justice survey carried out over a decade found that 66% of people released from state prisons in 24 states were rearrested within three years, and most of those were incarcerated again.
Mjland said Norway's incarceration system is based on the principles that people should be "treated decently by well-trained and decent staff" and have "opportunities for meaningful activities during the day" - something he called the "principle of normality" - and that they should retain their basic rights.
Mjland, whose research has focused on punishments and prisons, said that, for instance, prisoners in Norway retain the right to vote and access services such as libraries, health care and education delivered by the same providers working in the wider community.
Norway also operates open prisons, some on islands where there is a lot of farm work and contact with nature. The most famous is on the island of Bastoey, "which is very beautifully located in the Oslo Fjord," Mjland said.
Even Anders Behring Breivik - who killed eight people in the 2011 bombing of a government building in Oslo, then gunned down 69 more at a holiday camp for left-leaning youth activists - has a dining room, fitness room and TV room with an Xbox. His cell wall is decorated with a poster of the Eiffel Tower and parakeets share his space.
The idea of creating normal, humane conditions for people in prison is starting to spread in the U.S. as well.
Menendez brothers' former Beverly Hills mansion attracts curiosity seekers
The Pennsylvania Department of Corrections, for instance, has in recent years been trying to apply certain elements of the Nordic approach, and unveiled a program it calls "Little Scandinavia" in a prison in Chester in 2022.
The Menendez brothers' case was again in the public spotlight Thursday when the Los Angeles County district attorney recommended that their life-without-parole sentences be thrown out. Prosecutors hope a judge will resentence them so they can be eligible for parole.
If the judge agrees, a parole board must then approve their release. The final decision rests with the California governor.
Their lawyer and the LA district attorney argued that they have served enough time, citing evidence that they suffered physical and sexual abuse at the hands of their entertainment executive father. They also say that the brothers, now in their 50s, are model prisoners who have committed themselves to rehabilitation and redemption.
Both point to the brothers' years of efforts to improve the San Diego prison where they have lived for six years. Before that, the two had been held in separate prisons since 1996.
ALSO SEE: Menendez brothers' uncle says they should not be released
Menendez brothers' uncle says they should not be released
In 2018, Lyle Menendez launched the beautification program, Green Space, at the Richard J. Donovan Correctional Facility. His brother, Erik Menendez, is the lead painter for a massive mural that depicts San Diego landmarks.
"This project hopes to normalize the environment inside the prison to reflect the living environment outside the prison," Pedro Calderón Michel, deputy press secretary for the California Department of Corrections and Rehabilitation, told the AP in an email Friday.
The Menendez brothers' work is ongoing, with the ultimate goal of transforming the prison yard "from an oppressive concrete and gravel slab into a normalized park-like campus setting surrounded by a majestic landscape mural," according to the project's website.
The final product will include outdoor classrooms, rehabilitation group meeting spaces and training areas for service dogs.
The prison system recently launched the "California Model" in the hopes of bringing similar projects across the state to build "safer communities through rehabilitation, education and reentry," Calderón Michel wrote.
The brothers' lawyer, Mark Geragos, said he believes Lyle Menendez learned about the Norwegian model during his university classes. Lyle Menendez is currently enrolled in a master's program where he's studied urban planning and recidivism, and Geragos said his client hopes the beautification will make reintroduction into society easier for people who are paroled.
"When you're there in a gray space that is not very welcoming, it's disorienting to some degree," Geragos told The Associated Press on Friday. "And also you have the issue that the terrain is not something that's welcoming or helpful in terms of being acclimated and being re-acclimated into a community."
RELATED: New audio released of Menendez brothers behind bars as DA says he'll review new evidence
Could the Menendez brothers have a chance at a new sentence?
Dominique Moran, a professor at the University of Birmingham in the U.K. said she found in her research that introducing green spaces in prisons improves the wellbeing of prisoners as well as correctional staff.
"Green spaces in prisons reduce self-harm and violence, and also reduces staff sickness," said Moran, author of "Carceral Geography: Spaces and Practices of Incarceration."
Moran has studied prisons around the world, and said in an emailed statement that in the Scandinavian approach, "people go to prison AS punishment, not FOR further punishment."
"The deprivation of liberty is itself the punishment," she said. "There should not be further punishment through the nature of the environment in which people are held."
Gera reported from Warsaw, Poland, and Dazio from Los Angeles. David Keyton contributed from Berlin.