HOUSTON, Texas (KTRK) -- A Houston man was sentenced to life in prison this week for fatally shooting his ex-girlfriend in 2020 while he was on deferred adjudication probation for setting his ex-wife's home on fire, Harris County District Attorney Kim Ogg announced.
Emmishae Kirby, 29, disappeared from west Houston in Sept. 2020 after investigators said she was seen leaving the 800 block of Country Place Drive. An extensive search was conducted for weeks before her body was found on Oct. 3, 2020, in the Bear Creek Park area.
WATCH: Father of Kirby speaks out
Javon Gilbert, 31, a man prosecutors described as Kirby's ex-boyfriend, was charged with her murder.
According to authorities, Gilbert and Kirby had been living together until Sept. 2020, when they broke up after she accused him of sexually assaulting her. Gilbert moved out, but according to a witness, he broke into her apartment after the break-up, stood over her bed with a knife, and refused to let her go.
The video featured above is from a 2021 ABC13 report.
Prosecutors allege that Gilbert killed Kirby and dumped her body in a field near Bear Creek Park. But the life sentence all stems from a crime Gilbert committed years earlier.
In 2013, Gilbert was charged with arson for setting his ex-wife's home on fire while she was inside. The first-degree felony of arson carries a maximum punishment of life in prison.
Gilbert pleaded guilty in 2015 without an agreement, and Judge Frank Price sentenced him to eight years of deferred adjudication probation. If Gilbert had stayed out of trouble for eight years, he would not have had a conviction on his record, authorities state.
Instead, the district attorney's office says he killed his ex-girlfriend in 2020, which led prosecutors to file a motion to adjudicate guilt for the arson charge. After hearing the evidence against Gilbert in a four-day hearing, including that he reportedly killed Kirby and dumped her body in a field near Bear Creek Park, state District Judge Brian Warren revoked his probation and sentenced him to life in prison. Because it is the maximum sentence, Gilbert must serve at least 30 years in prison before he is eligible for parole. If he is ever paroled, he will always be under the supervision of a parole officer.
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Timeline of Kirby's disappearance
Prosecutors said there were multiple instances of Gilbert showing up at Kirby's apartment unannounced and peeking into her windows.
Text messages reviewed by officers from Kirby's account allegedly showed that on Sept. 5, Kirby told Gilbert she felt unsafe and that he responded he wouldn't harm her.
Police say Gilbert did not deny the text messages or breaking into her home. He also admitted they broke up because of the sexual assault accusations.
Further, when officers spoke to Gilbert, he said he hadn't returned to Kirby's apartment since Sept. 18, the last time she is seen alive on surveillance video with him.
During a later interview on Jan. 7, 2021, investigators say Gilbert admitted that he showed up uninvited on Sept. 18 because he wanted to see Kirby.
Officials reviewed extensive surveillance video and saw Kirby getting into her car with Gilbert in the passenger side. It's believed they went to a restaurant and gas station.
Authorities say Gilbert killed Kirby in the apartment, before disposing of her body in the Bear Creek Park area, about six miles away.
Gilbert was also seen making several trips back and forth from Kirby's building to the parking lot.
Prosecutors say that on Sept. 19, from 1:40 a.m. to 1:46 a.m., Gilbert was seen carrying a large item from the direction of Kirby's apartment and sitting it on the ground between vehicles in the parking lot.
The item appeared to have substantial weight. Prosecutors say that Gilbert was also on camera opening the rear of Kirby's car, picking up the item, placing it inside and leaving. He returns within an hour, parking Kirby's vehicle in a parking spot on the far side of the complex.
Further surveillance video shows Gilbert taking trips to Kirby's apartment and throwing items into a nearby dumpster, including a sofa, investigators said.
Police believe there's clear evidence that Kirby was killed shortly after returning to her apartment with Gilbert on Sept. 18, the last night they were together, the last date anyone spoke with Kirby on the phone and the last time she is ever seen on surveillance video.
Prosecutors say Gilbert also made a series of false, misleading statements during the investigation and continued to return to Kirby's apartment after her death to dispose of items.
He is also accused of destroying evidence related to the murder, including cell phone records, location records, and financial records.
According to investigators, Gilbert returned to the apartment on Sept. 19 to return Kirby's debit card.