In June 1986, Thomas arrived on death row which was then located at the Ellis One Unit, in Huntsville, Texas.

He was in a state of shock. He couldn't believe he had been sentenced to death. He was still extremely weak after he had been shot down by the police during his arrest and seriously wounded. And he was in shock with the prospect of his fatal destiny.

The first years on death row were terribly difficult for Thomas. However, he decided to do all he could to make a difference, both for himself and for his fellow inmates. What has played a determining role for Thomas in achieving this has been his religion and his faith. He began to consciously apply the teachings of his religion to "uplift fallen humanity", while studying himself, observing and studying human behaviour, and by being conscious about his own thoughts, communications and acts, as he continued to grow and evolve as a human being.

During the 14 years he spent at the Ellis One Unit, Thomas was able to strike up some very strong friendships with other inmates (to be posted soon: inmates' testimonials).

He also started to correspond with many people, from all over the world, and many of these contacts have become long-term friendships, some of them lasting for more than 20 years now.

To his many friends, Thomas spoke about how important it is to think positively, no matter how bad your situation in life seems to be. Positive thinking, or "uphill thoughts" as he called it, should be the very foundation for every human being's life, and we should all strive to get rid of negative thinking or "downhill thoughts", as negative thinking is the root of everything bad in this world. During these years in Ellis One Unit, he became more and more involved and engaged in helping and supporting his fellow inmates, especially the young ones. He said that by helping other inmates to change themselves, he found the very purpose of his life on death row.

During these years, Thomas often wrote that "those who haven't reached their deepest depths can neither reach their highest heights". An experience he personally went through during those years as he was faced with death on several occasions with many scheduled execution dates, and by witnessing many of his friends on death row being taken away to be executed. Nonetheless, these experiences did not make him bitter or angry nor filled with hatred. Instead, he continued to speak about the importance of cultivating "uphill thoughts" and that Love is the only thing that really matters.

Thomas has initiated many progressive projects concerning death row, such as the "Lamp of Hope" project, whose purpose was it to educate the public about the death penalty and alternatives, and to support victims' families as well as prisoners' families.

He was also one of the founders and vice-president of the "Death Row Journal". This newspaper was meant for the death row community, friends and families. Inmates could publish requests for penpals, articles and poems, or tributes to their executed friends. There were also articles about the various death row cases. And in each issue, there was always an updated list of the scheduled executions, which was very important since most of the numerous death row inmates (around 350 men) never received news from the outside, so this newspaper was their only way to be updated about what was going on.

Thomas taught some men how to read or write, as some inmates cannot read or write or even speak English. This situation can be fatal for men who must fight for their lives and must be able to adequately follow their case throughout the various appeals and legal proceedings.

Thomas did everything he could to comfort and support the families of death row inmates; and while still at Ellis, Thomas got the idea of establishing the Heritage House. This should be a place where the loved ones of death row inmates could find an affordable accommodation and spend the night, and where all could get together for mutual support and inspiration, seeking to overcome the hardships and to fight the cruel heritage of the death penalty, replacing hatred with love. In 1998, the Heritage House was established next to the house of Thomas' wife, Dorothy. She lived in the outskirts of Huntsville, close to Thomas on death row. Many visitors to death row from the US and abroad, including journalists, came to the house and met, and many spent the night or nights there. The house run on donations, and Thomas specifically wished that loved ones of inmates with an execution date should be accommodated freely.

Even after death row was moved to Livingston, an hour's drive from Huntsville, the Heritage House continued to function as a meeting place, and Dorothy picked up visitors from the airport and also drove them to death row in Livingston for visits. After death row was moved, many preferred to stay closer to the prison in Livingston, but a few close friends and visitors continued to stay there - however, not enough to keep the house going. For this reason, unfortunately, the Heritage House had to close down.

The living conditions at the Ellis One Unit were very harsh, but death row inmates could still communicate, work, recreate and socialize between them.

On March 2000, Texas Death Row was moved from Ellis One Unit to the maximum-security prison Allen Polunsky Unit in Livingston. Since then, the living conditions have become rougher for the death row prisoners. They are isolated and locked up alone in a tiny cell 23 hours a day. They cannot have any physical contact with each other nor with their family members when they come to visit them. Physical contact is forbidden even during the last visit, which takes place the morning of the day of the scheduled execution (which, most of the time, are carried out at 6:00 pm). Indeed, during visits, inmates and visitors are separated by a thick bulletproof glass and they can only communicate through a phone.

Thus, inmates on Texas Death Row cannot socialize, which is essential for any human being. The social, sensory and sleep deprivation that they endure are all obviously meant to dehumanize them.

"Everything dies here on Texas Death Row. From your emotions, to your ambitions, your dreams, your memories, your plans, your goals, your associates, your neighbors, your cell partners, your creativity, your ideas, your thoughts, your hope, your faith, your mind, your spirit, and then you will to live. After that, they finally kill your body. Nevertheless, some of the most Beautiful Flowers grow in some of the worst places". (From "A True Book from Texas Death Row" by Thomas J. Miller-El)

Despite the horrible living conditions on death row, Thomas has kept searching for meaning and value in his situation and circumstances, and somehow found the emotional stability and mental sanity necessary to cope with it all. Again, he has found very much solace in helping other prisoners.

Indeed, Thomas has constantly sought to provide  his fellow inmates with moral, spiritual, psychological, legal, academical, economical or whatever support he could.

This task was much more difficult at the Polunsky Unit because death row prisoners were completely isolated and couldn't communicate directly anymore nor have any contacts. They could only communicate with the prisoners who were housed in the same pod, by shouting. As a consequence, Thomas received many letters every day, and at least half of them were from fellow inmates who were seeking his support, advice or mentoring, which he provided them as much as he could, through letters. This avenue of communication was then prohibited too and prisoners could no longer write to each other.

When Thomas met inmates in the visiting room who had an execution date, he was always very supportive and encouraging, doing all he could to keep their and their families' spirits up, while his heart was breaking over seeing them and their family in deep pain.

Some prisoners never receive visits. This is why, when his friends visit him, Thomas encourages them to also visit some other inmates he knows, who would very much like or need to receive visits.

Thomas left death row on August 29, 2005.