"48 Hours" has the latest on Kevin Cooper's battle for his freedom in "The Troubling Case of Kevin Cooper" airing Saturday, March 21 on CBS.

As a "48 Hours" producer, I have met and interviewed convicted felons. I had never met a death row inmate — until I visited Kevin Cooper at San Quentin Prison.

Correspondent Erin Moriarty and I completed the required paperwork in preparation for our visit. The California Department of Corrections has strict rules for visitors which includes a dress code: flat shoes, no jewelry, no skirts or dresses, no khaki-, blue- or green-colored clothing.

Erin and I decided to wear black — easy and uncomplicated.

I told a defense attorney friend I was going to visit death row inmate Kevin Cooper. He asked me to call him after the visit. I agreed.

It was a Thursday. May 9, 2019. Erin, Cooper's attorney, Norman Hile, and I arrived at San Quentin prison at 7 a.m. We stashed our personal belongings in lockers at the visitor center and then proceeded to the security checkpoint. We we were given nametags and escorted to the visitor area. "48 Hours" has been covering the Kevin Cooper case for more than 20 years and this visit would be the first time our team would meet him face to face.

When the door opened, I walked in, turned to my right, and saw Kevin Cooper standing in a plexiglass room with bars. This is where we would visit Cooper. When we entered the room, a corrections officer removed his handcuffs and Cooper greeted us with a smile and a handshake.

From left, "48 Hours" producer Marcelena Spencer, Kevin Cooper and "48 Hours'" correspondent Erin Moriarty during the visit to San Quentin State Prison in May 2019. California Department of Corrections and Rehabilitation

There were no corrections officers in the room during our visit. We sat in plastic chairs with a small table between us. The furniture reminded me of a late 1970s elementary school library.

We talked for several hours. Cooper did not mince words. He wanted Erin and me to understand why he has been fighting so hard to clear his name. In 1985, Cooper was convicted of the murders of four people in Chino Hills, California. I had read the letters he had sent Erin over the years but to see and hear Cooper's story in person was even more compelling. San Quentin prison does not allow the media to record inmate visits. I wish we could have recorded it to share with our viewers.

During our visit I couldn't help but take in the surroundings. It was stark and surreal. There were more visitors' rooms. The men were enclosed in small boxes with bars and the overwhelming majority looked like Kevin Cooper: black and brown with salt-and-pepper hair. Books like "Just Mercy" and "The New Jim Crow" examine the justice system and mass incarceration, but now I was seeing it up close: men of color growing old behind bars.

I wasn't afraid. I wasn't having an internal debate about guilt or innocence. I knew nothing about these men or the circumstances of their crimes, yet I began to feel anxious. The visit was a reality check because I am a journalist and I'm African American.

Cooper, who has always claimed he is innocent, looked me in the eye and said, "I have been here for a long time." I responded, ''More than half your life." I sensed Cooper knew I was taking in the demographics of the prison population. We never talked about it. We didn't need to.

At the end of our visit we took Polaroid photos and said goodbye. The corrections officer that had removed the handcuffs put them back on Cooper.

Erin, attorney Norm Hile and l left San Quentin. Later that day, I phoned a friend of mine who is a defense attorney and is also African American. He didn't ask me about the details of the visit; he wanted to know if I was OK. I said I wasn't sure and that I needed to wrap my brain around it. Nearly a year later, I am still processing.