In June 2020, the months-long search for missing Fort Hood solider Vanessa Guillén came to a tragic end when her dismembered remains were found buried in a remote area near the Leon River in Bell County, Texas.
It was later determined that the 20-year-old private first class had been beaten to death with a hammer by a fellow soldier, according to authorities. Investigators believe Guillén was killed on April 22, 2020, the same day she vanished, by U.S. Army Specialist Aaron Robinson, 20, at the Fort Hood military base, where they were both stationed.
While Robinson died by suicide in July just as authorities were closing in on him, his girlfriend, Cecily Aguilar, has since been charged in connection with the case. She later pleaded not guilty to one count of conspiracy to tamper with evidence and two substantive counts of tampering with evidence.
The investigation, which will be featured in season two of Oxygen's "Injustice with Nancy Grace," is still ongoing. Throughout the series, Grace, one of television's most respected legal analysts, shines a light on investigative and legal injustices, bringing her unique perspective to some of the most complex and current true crime stories.
Catch up on the Guillén case below before tuning in to the series premiere on Thursday, October 8 at 9 p.m. ET/PT on Oxygen.
1. Guillén Was Sexually Harassed Before She Vanished, According To Family
After Guillén vanished from the Regimental Engineer Squadron Headquarters — leaving behind her car keys, barracks room key, identification card, and wallet in an armory room — her mother told the media that Guillén had been sexually harassed by a sergeant.
In the weeks prior to her disappearance, Guillén said she did not feel safe at the base, calling it "evil," and that she was having trouble sleeping. She also said that the sergeant had followed her when she went jogging.
“[Vanessa] said it was stalking and verbal harassment. He would look at her [in] some type of way that would make any woman feel uncomfortable,” Gloria Guillén, who speaks Spanish, said through a translator.
Guillén, however, did not reveal the sergeant's name to her mother, who told her to report the harassment, saying she wanted to handle the situation on her own.
Maj. Gen. Donna Martin, the Army’s provost marshal, later told ABC News' "20/20" that in their criminal investigation, they "found no evidence of sexual harassment between Vanessa and Spc. Robinson ... That was ruled out very early.”
2. The Prime Suspect Shot Himself
A witness told investigators that on the day of her disappearance, Guillén left the armory where she worked to go to another arms room that was being supervised by Robinson to confirm serial numbers for weapons and equipment, according to the criminal complaint obtained by the Killeen Daily Herald in Central Texas.
When interviewed by authorities, Robinson claimed that Guillén had left the arms room and had walked toward the motor pool when he last saw her. Thee soldiers also reported that they had spotted her at “a time that would’ve indicated she had left Spc. Robinson’s arms room” before she vanished.
“That led us to the parking lot, where they said they saw her walk,” Martin told “20/20." “We did a lot of investigation out into parking lot to see, maybe if she had been abducted [there].”
Robinson claimed he spent the rest of the night with Aguilar, and the investigation hit a dead end until authorities looked through Robinson's phone records, which showed he had called Aguilar multiple times the night Guillén went missing.
While Aguilar initially claimed she had asked Robinson to call her because she had lost her phone and was trying to find it, she later reportedly admitted that Robinson had called her that evening and told her that he killed a woman at the arms room.
Aguilar allegedly told investigations that Guillén had “never made it out of the Army alive."
Investigators also discovered that Robinson’s phone had pinged in the same area where Guillen’s remains were found in the early morning hours following her disappearance, according to a criminal complaint.
When Robinson saw media reports that Guillén's body had been uncovered on June 30, 2020, he fled the base, according to investigators. Authorities gave chase and were able to stop him, but as law enforcement closed in, Robinson shot himself, reported ABC News.
3. The Suspect's Girlfriend Has Been Charged In Connection With The Case
Following the murder, Robinson reportedly concealed Guillén's body, and witnesses saw him pull a large “tough box” out of the arms room and load it into his truck. He then dropped the box off near Leon River and picked up Aguilar at her work, taking her to the dump site, according to a criminal complaint.
The complaint alleges that Robinson and Aguilar used a hatchet or ax and a machete-type knife to remove Guillén's limbs and head. They reportedly lit the body on fire, but when it would not burn completely, they placed it in three separate holes and buried the remains, according to investigators.
Aguilar was charged with one count of conspiracy to tamper with evidence and two substantive counts of tampering with evidence, according to a press release from The United States Attorney’s Office Western District of Texas. If convicted, she faces up to 20 years in federal prison.
Aguilar has since pleaded not guilty.
4. The 'I Am Vanessa Guillén Act' Has Been Introduced
On Sept. 16, 2020, lawmakers introduced the bipartisan "I Am Vanessa Guillén Act," which aims to transform the way sexual harassment and sexual assault allegations are handled within the military.
The act would classify sexual harassment within the Uniform Code of Military Justice as a crime, and it would allow third-party investigations into sexual harassment and sexual assault claims made by U.S. service members, according to CNN.
“It’s not fair that this had to happen to Vanessa for everyone to pay attention,” Guillén's sister, Mayra Guillén, said at a news conference, according to The Washington Post. “She is now an American hero that will save lots of lives.”
To lean more, watch season two of "Injustice with Nancy Grace," premiering Thursday, October 8 at 9 p.m. ET/PT.
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