A Houston man who made headlines when he was caught on camera carjacking an elderly couple in Briar Forest and then committing a murder on the same day was sentenced to 80 years in prison by a Harris County jury, District Attorney Kim Ogg announced.

“This was not an isolated incident — this man was intentionally and deliberately using a gun to threaten, steal and kill,” Ogg said. “His actions affected so many people in such terrible ways that the only just resolution is that he spend decades in prison.”

Michael Coates, 21, was convicted of murder on Friday for shooting 29-year-old Marcus Mercado, a father of two, during a midday altercation on Feb. 11, 2023, near a convenience store at the 9800 block of Meadowglen Lane.

At about 12:30 p.m., witnesses said, Mercado approached Coates near the store where Coates was known to sell drugs, and the two began to argue. Then Coates pulled a pistol and shot Mercado three times. Surveillance video shows that Mercado fell to the ground and was waving his arms around as Coates came closer, stood over him and shot him three more times, all in the head.

Coates then ran away and ended up in west Houston about two hours later. There he was caught on video pulling a gun on a 75-year-old woman outside her garage and demanding the keys to her car.

She screamed, and her 77-year-old husband came out of the house to help. Coates pointed the gun at him and demanded the car keys.

The couple gave him the keys, and he drove away. They called the Houston Police Department, which was already investigating the murder. The car was found abandoned on a residential street about two days later.

Three days after the murder, Coates was involved in another armed robbery in which he stole a man’s wallet, car keys and backpack with a laptop computer.

The man contacted the Harris County Sheriff’s Office, and investigators were able to track his laptop to Coates’ apartment in the 3200 block of Gessner. Deputies executed a search warrant at the apartment and found a Glock 9mm semiautomatic pistol that proved to be the murder weapon that killed Mercado.

Police later released video of Coates robbing the elderly couple to get the public’s help in apprehending him. He was arrested on March 22, 2023.

During his murder trial, jurors also heard about those crimes before they made their decision on punishment.

Assistant District Attorney Nancy Ta, who is a chief in the DA’s trial bureau, and Bryan Honeycutt, a chief in the Major Offenders Division, prosecuted Coates.

“The defendant did this in broad daylight, then ran from the police and later claimed self-defense, which the jury was smart enough to recognize was not true — it was an attempt at an excuse for murder,” Ta said. “And when the jury heard about the other armed robberies, the other victims and all of the families of the victims who were affected, they made the right decision.”

Coates will have to serve at least 30 years in prison before he is eligible for parole.

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