Vanessa Guillen murder: Was cellphone photo the motive behind brutal Fort Hood slaying?

FORT HOOD, Texas — The Fort Hood soldier who murdered and dismembered Pfc. Vanessa Guillen in April 2020 did so because Guillen spotted his married girlfriend’s photo on his phone, court documents allege.

Aaron David Robinson grabbed a hammer on April 22, 2020, and bludgeoned Guillen, 20, of Houston, to death in an arms room on the Texas military base, authorities said. Guillen, who joined the Army in 2018, was posthumously promoted to specialist a couple of months later.

According to Robinson’s girlfriend, Robinson then sexually assaulted Guillen’s lifeless body. Her remains were found burned and hacked into pieces on June 30, 2020, along the Leon River near Belton, where Robinson and his girlfriend, Cecily Anne Aguilar, had encased them in concrete and buried them.

Robinson, 20, fatally shot himself hours later as city and federal investigators closed in to make an arrest.

Editor’s note: This story contains graphic details of a violent crime.

The disturbing new details in the case come from a Texas Department of Public Safety report that was filed May 19 in federal court. Records show that the document was sealed by the judge, but not in time to stop multiple news outlets from accessing the report.

Aguilar, 23, is seeking to have her alleged confession thrown out. She has been charged with 11 counts, including tampering with evidence, being an accessory after the fact and making false statements to law enforcement.

The Department of Public Safety report provides a glance at a possible motive for Guillen’s killing. According to investigators, Aguilar “claimed Robinson would go into moods in which he would not be his normal self and have a ‘tic.’”

“Aguilar later explained why Robison killed Guillen, saying Guillen saw Robinson’s cellphone lock screen, which contained a picture of Aguilar,” the document states. “He told her he was worried about getting in trouble for violating the Army’s fraternization rules since Aguilar was still married to another soldier, and he hit Guillen in the head with a hammer.”

Guillen’s autopsy showed she had multiple blunt force injuries to the skull, in addition to burn damage. Extensive bone fracturing, sharp force damage “and one likely saw cut” found on the remains were consistent with dismemberment.

The report also gives graphic details of how Aguilar said she and Robinson used a machete, an axe, an Army entrenching tool and two knives to dismember Guillen and “cut her flesh from the bones.”

Over two visits to the makeshift gravesite, the pair cut Guillen’s body into pieces and placed them and her clothing in a black military-style tote box, which they then burned. They buried her body in multiple holes with plans to return in a few days.

“The second time Aguilar and Robinson went to the location, they further dismembered Guillen’s body … and burn(ed) as much as they could,” the report states. “Then they buried the bones and put cement over the bones so they could not be found.”

The hope, Aguilar told authorities, was that Guillen’s remains would not be found for several years. That hope was dashed June 30 when a man repairing a nearby fence came upon one of the holes in which Guillen had been buried.

A charred piece of the tote was also found.

It was unclear from the report if Guillen’s autopsy corroborated Aguilar’s claim that Robinson sexually assaulted the slain soldier. According to investigators, Aguilar confessed her involvement in the killing to a fellow inmate at the Bell County Jail.

The woman, Kristen Chapa, asked Aguilar about allegations that Robinson may have raped Guillen before her murder. Aguilar told her he had not — but said he did so after Guillen was dead, the court documents state.

“Chapa asked Aguilar how she (Aguilar) knew about the post-mortem rape,” the report states. “Aguilar would not say exactly, but looked Chapa in the eye and said, ‘I know.’”

Aguilar is currently being held as a federal inmate at the McLennan County Jail in Waco.

Guillen’s sister, Mayra Guillen, told ABC13 in Houston last week that her family was enraged when reading Aguilar’s latest account of what took place the night her sister was slain.

“There is no credibility to Cecily Aguilar’s words, and it’s a shame that there’s an opportunity for this criminal to defend herself after what she did to my sister’s body,” Guillen told the news station. “Cecily Aguilar will try everything in her power to walk freely, as we are being denied the truth at this very moment.”

Guillen said her sister’s loved ones are eagerly awaiting a trial so the public will know the truth about what happened to her sister, whose disappearance in April 2020 was shrouded in mystery.

She said her sister, a small arms and artillery repairer for the 3rd Cavalry Regiment, would not have reported Robinson’s affair with Aguilar, which violated the Army’s fraternization policies. Aguilar was married but estranged from her husband, who was also a soldier at Fort Hood.

“My sister was a very responsible person that would not meddle into Robinson’s and Aguilar’s alleged ‘relationship,’” Guillen said. “We truly hope Vanessa receives justice. No family deserves to go through this.

“Vanessa should be here today, defending her loved ones and her country.”

The latest report adds to a narrative that began April 22 when Vanessa Guillen vanished from Fort Hood. According to authorities, she was last seen around noon in the parking lot of the Regimental Engineer Squadron Headquarters, where she worked.

>> Related story: She ‘never made it out of the Army alive,’ suspect in Vanessa Guillen murder states

Investigators learned that Guillen had left the arms room where she was working to go to a separate arms room to confirm serial numbers for weapons and equipment on which she was working. Both rooms are located in the basement of the barracks where Guillen lived.

Robinson was in charge of the arms room to which she was going that day, according to a criminal complaint in the case.

Guillen never returned to her workspace, leaving her belongings behind. A colleague told investigators her wallet, ID and keys were still there when he locked up for the day, according to the documents.

“A search of Pfc. Guillen’s phone records revealed the last outgoing text message from her phone was a message to Spc. Robinson’s phone,” FBI special Agent Jonathan Varga wrote in a 2020 affidavit. “Spc. Robinson was one of the last people known to have seen Pfc. Guillen.”

Robinson told investigators the contact involved the serial numbers for the equipment Guillen was working on. He claimed he gave her paperwork and the serial number of a .50 caliber machine gun which needed to be serviced.

Robinson said he did not conduct any “small talk” with Guillen, whom he said he knew only through their job functions.

“He said she left the arms room and he believed she would have next gone to the motor pool,” the previous affidavit states. “Witnesses at the motor pool prepared to receive the paperwork from Pfc. Guillen stated she did not arrive with the papers.”

When interviewed by CID agents April 28 regarding Guillen’s disappearance, Robinson told them he went home from work the day of her abduction. He lived off-post with Aguilar.

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Robinson said he remained home the rest of the evening except for a brief trip to the base around 6:30 p.m. to use a government computer to sign up for some training.

Witnesses came forward, however, and told detectives they had seen Robinson on the base the night of April 22, moving a large, heavy tote box from the arms room and into the back of his car.

Those witnesses were Aguilar’s estranged husband, Keon Aguilar, and a friend, the recent court documents state. Keon Aguilar told investigators he and his friend had returned from getting food the night of April 22 and parked across from the barracks, near the entrance to the armory in the basement.

As they parked, he spotted Robinson’s silver Chevrolet Impala parked nearby. Robinson was coming out of the armory with a large black “Pelican case,” a lightweight but impact and water-resistant case favored by the military.

Robinson struggled to get the case into his car, the report states.

“Keon was suspicious because he felt like there would have been no reason for Robinson to take the case unless he was stealing tools,” according to the document.

The tote, which was one of several located inside the barracks, was similar to the charred pieces found at Guillen’s burial spot 26 miles away.