Ponchai Kamau Wilkerson, of African-American and Thai descent, was born in Houston, Texas. While little is known about his early childhood, he grew up in the Fort Bend-Houston area, east of Missouri City, Texas. He attended public schools in the Fort Bend Independent School District and graduated from Willowridge High School in 1990.

On November 28, 1990, Wilkerson and Wilton Bethony entered Yi Chung Myong’s Royal Gold Jewellery Store in Houston, Texas. They had been on a month-long crime spree. Wilkerson left the store twice but returned the second time with a Glock pistol. Without warning, he fired a single shot at Myong’s temple from a distance of about 12 inches (30 cm), killing him instantly. During the trial, Wilkerson admitted the murder was neither in self-defense nor accidental.

The Texas Court of Criminal Appeals upheld his conviction and sentence on December 12, 1994. He later appealed to the United States Court of Appeals for the Fifth Circuit and the Supreme Court of the United States, but both denied his appeals.

On Thanksgiving Day in 1998, Wilkerson and six other death row inmates attempted to escape prison. One inmate, Martin Gurule, successfully got out but was shot and drowned shortly after. Wilkerson and the other inmates eventually surrendered.

In February 2000, Wilkerson exhausted his final appeal in a courtroom incident where community activist Njeri Shakur protested the proceedings. Shakur, a member of the Texas Death Penalty Abolition Movement and the Allen Parkway Village Residents Council, was charged with contempt and sentenced to 30 days in jail. While on death row, Wilkerson developed friendships with Shakur and Deloyd Parker Jr., the founder of the S.H.A.P.E. Community Center.

On February 12, 2000, Wilkerson and fellow death row inmate Howard Guidry took 57-year-old prison guard Jeanette Bledsoe hostage at the Terrell Unit (now Allan B. Polunsky Unit) near Livingston, Texas. Wilkerson had somehow managed to unlock his cell door. Members of the National Black United Front and the S.H.A.P.E. Community Center urged him to release the guard. After a tense 13-hour standoff, Bledsoe was freed unharmed.

On the day of his execution, Wilkerson refused to leave his cell, forcing guards to use Mace-like gas and carry him to the death van that transported him to the Huntsville Unit. He did not request a last meal or provide instructions for his body’s disposal. When asked for a final statement, he declared, "This is not a capital punishment case!"

As the lethal injection drugs were administered, Wilkerson unexpectedly spit out a universal handcuff and leg restraint key, measuring about an inch and a half. How he had obtained the key remained a mystery. Wilkerson was pronounced dead at 6:24 p.m.