A murder trial in the shooting of a transgender woman who was a well-known member of Austin’s LGBT community got underway Tuesday with the defense dropping the surprise that they agree their client is the shooter.

But JonCasey Rowell acted in self-defense, his lawyer insisted Tuesday in a brief opening statement that teased to evidence that will show "why Mr. Rowell had to use deadly force" when he shot Monica Loera in the early morning of Jan. 22, 2016, in North Austin.

Rowell’s attorney, Jeff Senter, did not give additional details and later declined to elaborate in a chat with reporters outside of the courtroom.

"The facts are developing as we speak, but we believe the facts will establish he is innocent," he said.

Attorneys for both sides agree that Loera, 43, died from a single gunshot wound to the neck after a confrontation with Rowell at the front door of the East Powell Lane home she shared with two others. Loera was working as a prostitute on the night she was killed, and Rowell had responded to her ad on backpage.com for sexual services.

Several witnesses who either lived with Loera or next door took the witness stand and gave similar accounts of what happened. After 2 a.m., Loera responded to a knock at the front door and brought with her a coat they believe Rowell might have forgotten at her place. About five minutes later, there was a louder knock. Loera’s roommate, who was sleeping in the living room on the sofa, said she again got up, but this time was annoyed, proclaiming, "I’m gonna make him leave this time."

An argument ensued, a witness said. The man yelled, "give it back to me." A loud bang followed, with one witness saying the sound resembled a firecracker and another saying it "was like a balloon popped." A neighbor testified that the man then got into a black pickup and drove east toward Interstate 35.

Medics arrived and took Loera to the hospital where she soon was pronounced dead.

Authorities connected Rowell to the shooting through cellphone records and a student ID that belonged to him, which they found in Loera’s bedroom. They also seized a pistol in his Williamson County trailer that they linked to a projectile found in the victim’s body. Rowell, a married father of a newborn, had been living in Georgetown for work while his family was in Childress in North Texas.

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None of the witnesses who testified could identify Rowell as the man who was at the front door, but did provide a physical description — medium height and built, and facial hair — that matches the 30-year-old. Loera’s roommates said they did not see her with a weapon when she went to the door.

In opening statements, prosecutor Beth Payan said Rowell deleted from his phone data displaying his activity around the time of the shooting, including a call to his wife in which he pleaded for her to cancel his credit cards because he lost his wallet. The wife will testify that Rowell then called her back and said he found the wallet, Payan said.

Loera’s sister testified that Loera has lived as David until her mid-20s when she began dressing as a woman and taking hormones to grow breasts. Money kept her from making a complete transition.

"She always said she was not gay or homosexual," Cynthia Loera said. "She believes she was a woman trapped in a man’s body."