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Trial of Boyfriend Accused of Killing Texas Cheerleader Goes to Jury

After a seven-day trial, a San Antonio jury must now determine whether to convict Mark Howerton, who is accused of killing his 19-year-old girlfriend Cayley Mandadi in October 2017.

SAN ANTONIO (CN) – After a seven-day trial, a San Antonio jury must now determine whether to convict Mark Howerton, who is accused of killing his 19-year-old girlfriend Cayley Mandadi in October 2017.

The Trinity University sophomore, a cheerleader and sorority sister, was taken off life support on October 31, 2017. Her autopsy revealed that she suffered a subdural hematoma, or a pooling of blood in the brain cavity, that caused her brain and heart to fail.

The question before the jury – comprised of seven men and five women – is whether Howerton is responsible for the hematoma, or if it was caused by a fall, the pair’s drug use at a music festival that weekend or an accident during “rough sex” Howerton claims the pair had in a parking lot while they were intoxicated.

“She had just turned 19 when she left for Mala Luna Music Festival with the defendant,” said state prosecutor Alessandra Cranshaw during her closing argument. “She was just beginning her life when she got into the car with that defendant … And she deserved more than this.”

Howerton’s defense counsel, John Hunter of Hunter Lane & Jampala, emphasized the state’s burden of proof.

“Mark’s not a killer. He’s not covering up some plan, some diabolical scheme. He’s not covering up some act of passion ... Mark’s not covering anything up,” Hunter argued. “Mark’s a 22-year-old boy, as you can see, probably, with the emotional intelligence of a boy who’s 15 or 16.” 

Witness testimony painted Howerton as a possessive, jealous boyfriend who would yell at Mandadi and shove her, take her phone and look through her photos and messages. Mandadi’s ex-boyfriend Jett Birchum told the jury last Friday that when she went to a fraternity party against Howerton’s wishes, the defendant sent her a video of himself putting a gun in his mouth with the caption: “this is your fault.”

“He’s not on trial for being a manipulative jerk. He’s on trial for murder,” Hunter said of Howerton in the defense’s closing argument. “The absence of evidence is something you are always obligated to favor and consider in favor of one person: Mark Howerton.”

On Oct. 29, 2017, the pair attended the Mala Luna Music Festival in San Antonio, where they drank heavily and took ecstasy, an empathogen also known as “molly” or “MDMA” consumed recreationally for its euphoric qualities. 

On their way to Houston after leaving the festival, they pulled over to have what Howerton described to investigators as “rough sex” in the parking lot of Whataburger’s corporate headquarters.

Howerton said that afterward, Mandadi seemed to pass out and was snoring loudly. He decided to continue to drive to Houston, a decision the prosecutors cast as a kidnapping, when he noticed that Mandadi stopped snoring and had no pulse or heartbeat. That’s when he drove to a hospital in Luling, Texas, about 60 miles east of San Antonio.

“We started this case last week with Sheryl Lane, the paramedic from Luling,” Cranshaw said. 

Lane approached Howerton’s Mercedes-Benz at the hospital, “opened the passenger side door and found the lifeless Cayley Mandadi sitting in the front seat with her pants down around her ankles, without a pulse, not breathing,” Cranshaw added.


Suzanna Dana, the forensic pathologist who performed Mandadi’s autopsy, concluded that she died of a subdural hematoma caused by blunt force trauma to the face and head.

During direct examination last week, Dana discussed dozens of images she took during the autopsy: close-ups of Mandadi’s injuries, photos of the muscle tissue between her scalp and brain, her brain removed from the cranium, and facial injuries. 

The facial injuries, Cranshaw said, were “to the front of Cayley’s face, they are to the sides of Cayley’s face and head – which makes sense when you’re getting assaulted in a vehicle.”

Hunter insisted that these injuries were noted long after medical procedures took their toll on Mandadi’s body.

“They have no idea what happened to Cayley Mandadi. There is no evidence of facial trauma at that admitting hospital,” Hunter said during his closing argument. “EMTs did not note facial trauma, the physician did not note facial trauma. There were six people in that room trying to assist with resuscitation efforts; not one of them noted facial trauma.”

The defense strove to cast doubt on whether Howerton was the source of the injuries that caused Mandadi’s hematoma. 

Hunter asked about the extent of resuscitation efforts performed on Mandadi: Howerton’s attempts at CPR while driving down the highway; her intubation at the Luling hospital and chest compressions that continued during the airlift from Luling to the Seton facility; the organ removal process’ inherent trauma to the body. 

“The evidence is entirely consistent [with] being received for autopsy … having been through the process of hospitalization, the process of organ collection,” Hunter argued Wednesday. “The kind of edema you see there is not proof of sexual assault.”

Prosecutors took aim at Howerton’s character.

“He’s so angry, he’s so possessive, he’s so controlling,” Cranshaw said in the state’s closing argument. “[Her friends] know Cayley’s with him. So he doesn’t get a pass for taking her to the hospital lifeless, with her pants around her ankles.”

Birchum says he saw Howerton and Mandadi for about half an hour at Mala Luna before they left for Houston Sunday. He recalled the last time he saw Mandadi alive.

“Cayley looked like she was trying to create space and kinda just get away. And it looked like they were having an intense conversation,” Birchum testified Friday. “As she’s trying to step away, I see him reach out his right arm, hook it around her shoulder and pull her in closer,” and then they walked to the parking lot, he said.

Birchum, who was promised immunity if he testified in this case, repeatedly asserted his Fifth Amendment right to remain silent when Hunter cross-examined him about photographs of controlled substances, including cocaine being snorted from his penis, whether he was a drug dealer on campus and about a Title IX sexual assault investigation initiated against him by Trinity University before he transferred to Texas State University.

Hunter also argued that Birchum’s testimony about seeing Howerton and Mandadi at the festival was completely fabricated: Digital forensics experts interpreted GPS and cell tower data location recovered from Birchum, Mandadi and Howerton’s phones indicating that when Birchum called Mandadi, her phone was miles across town.

The cell phone data was also consistent with Howerton and Mandadi never going into the festival at all on Sunday, in contradiction of not only Birchum’s testimony on the stand but also Howerton’s claims to law enforcement officials. Both men say they saw one another at the festival Sunday. This loose thread was not conclusively resolved by either the prosecution or the defense. 

As Hunter had explained to potential jurors during voir dire last Monday, the burden of proof was on prosecutors to show that, “but for” Howerton’s engaging in an act “clearly dangerous to human life” of committing some other felony – such as sexual assault or kidnapping – Mandadi would still be alive.

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