A beloved pregnant mom was murdered at home. Her husband was having an affair. Did he kill her?

Belinda Temple was a pregnant mother and teacher who was found shot to death in her Texas home 20 years ago. Who wanted her dead?

Her husband, who was having an affair and allegedly wanted to make room for his mistress? A student who was angry with her? A still-unknown perpetrator who may have broken into the residence?

Jurors are being asked these questions right now.

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This week, a new trial started in the criminal prosecution of Temple’s husband, David Temple, who is accused of murdering his wife in 1999, People reports.

David Temple had been convicted of the slaying in 2007 and spent nine years in prison, but his conviction was overturned several years ago because of prosecutorial misconduct. An appeals court found Temple didn’t get a fair trial the first time because prosecutors withheld evidence that could have been consistent with his claim that a burglar killed Belinda.

Temple was subsequently released on bond and prosecutors decided to retry the case.

On January 11, 1999, Belinda, almost eight months pregnant, had left Katy High School where she was a special education teacher, and drove home to David and their 3-year-old son, Evan, who was sick.

The 30-year-old was later found in the master bedroom closet of the home, shot execution-style.

During this week’s court proceedings, the prosecution argued and the defense acknowledged that David Temple was having an extramarital affair with Heather Scott, who also was a teacher. The two married two years after Belinda’s death.

“There was only one person on this Earth who had the motive, the means and the opportunity to cause her death,” prosecutor Lisa Tanner told jurors.

But Temple’s defense attorney, Stanley Schneider, refuted that claim.

“We’re going to go back in time,” Schneider said in court. “We’re going to hear a story of not one betrayal, but two betrayals.”

Schneider alleged that authorities failed to examine other potential suspects.

The prosecution claims Temple staged the scene to look like a home invasion, although notable items of value had not been taken. Temple’s defense team says one of Belinda’s students was angry with her and could have been the killer.

Defense lawyers, in an effort to poke holes in the state’s timeline, also allege that David and son Evan were captured in surveillance video at a grocery store shortly after the killing.

“David Temple did not have time to commit murder,” Schneider said. “He could not have gotten home.”

Prosecutors argue the store sighting was a fake alibi and that David had adequate time to commit the murder.

Meanwhile, three days into the trial, David’s wife, Heather Scott Temple, whom he was seeing while married to Belinda, filed for divorce, KPRC-TV reports.

Belinda’s father, Tom Lucas, has said he believes his wife died as a result of the stress tied to the case.

In 2017, Lucas contacted “Crime Stories” and asked Nancy Grace to investigate the death. At the time, she asked listeners to call authorities and advocate for a new trial with an independent prosecutor.

The new trial could last four weeks.

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