ABC News March 6, 2019

What happened when a Texas doctor was killed in an alleged murder-for-hire plot

WATCH: A successful Texas doctor and businessman finds love again at a dance class: Part 1

When a Texas doctor was found shot and stabbed to death, an investigation found that he might have been the victim of an alleged murder-for-hire plot by his girlfriend’s apparently jealous ex.

In 2012, Dr. Joseph Sonnier, a Lubbock, Texas, pathologist, was found murdered in his own home. Dr. Thomas Michael Dixon, a plastic surgeon from Amarillo, Texas, was eventually convicted of the murder in 2015.

Prosecutors argued that Dixon paid his friend David Shepard to stalk and then kill Sonnier because he was jealous that Sonnier was dating Dixon’s former girlfriend Richelle Shetina.

(MORE: Woman at the center of Texas doctors love triangle murder-for-gire case speaks for first time)

Though Dixon was found guilty and sentenced to life in prison without parole, he appealed, and his conviction was overturned in 2018. Today, Dixon, who was released on bond, is awaiting his retrial.

From the moment Dixon and Shetina first met to Dixon’s release from prison, here is a timeline highlighting some of the key events in the case.

2008

Lubbock Police Department
Richelle Shetina met Dr. Thomas Dixon after visiting Sensi Med Spa in Amarillo, Texas, for Botox injections.

Richelle Shetina meets Dr. Thomas Dixon after visiting Sensi Med Spa in Amarillo, Texas, for Botox injections. Dixon was the owner of the spa and administered the shots. They become friends on Facebook and developed a friendly relationship.

2010

Courtesy Richelle Shetina
Richelle Shetina's boyfriend Dr. Joseph Sonnier was found murdered on July 10, 2012.

Shetina and Dixon begin an affair. His wife finds out and quickly files for divorce. The couple begins dating exclusively but Shetina recalls their relationship as rocky. At one point, the defense would argue at trial, that Shetina thought Dixon might propose, but he bought her a tea-of-the-month club subscription instead. After months of highs and lows, Shetina breaks it off with Dixon.

2011

Courtesy Richelle Shetina
Richelle Shetina took dance classes at D’Venue Dance Studio in Lubbock, Texas, where she met Joseph Sonnier.

Shetina begins taking dance classes at D’Venue Dance Studio in Lubbock, Texas, in July 2011, where she meets a tall, handsome pathologist named Dr. Joseph Sonnier. Their friendship quickly turns into a romance that Shetina describes as the love of her life.

While Dixon is desperate to get back with Shetina, she lets him know by text message in September 2011 that she is now in love with her dance partner. The defense argued that Shetina was playing a cruel game and leading Dixon on.

Shetina and Dixon meet in person for the last time on Oct. 31, 2011. Shetina says Sonnier, then her boyfriend at the time, was aware of the meeting and that she decided to meet Dixon to show him that she was over him and never coming back.

February 2012

Courtesy Richelle Shetina
Like Joseph Sonnier, Richelle Shetina was divorced when the two met.

Shetina and Sonnier continue dating, taking trips to Los Angeles and a romantic vacation to Paris for her 50th birthday. While Shetina says they were very much in love, strange things seemed to be happening.

Courtesy Richelle Shetina
Richelle Shetina and Joseph Sonnier took a trip for her 50th birthday to Paris, France.

She says she felt like she was being watched at her local gym, and in February 2012, she came home to an odd note claiming to be from an ex-girlfriend of Sonnier. Shetina said Sonnier thought that it must be someone trying to “drive a wedge” between them.

July 2012

Lubbock Police Department
Joseph Sonnier's home is seen here in this crime scene photo.

Dr. Joseph Sonnier is stabbed and shot to death on July 10, 2012, as he arrives home from work. His body isn’t discovered until the next day when landscapers arrived to do work at the home.

Later that week, a man named Paul Reynolds contacts police and tells them that the man he is staying with, David Shepard, mentions that he killed someone in Lubbock. Reynolds tells police he did an online search and found information about Sonnier’s death, and thought he might have been Shepard’s victim.

(MORE: Inside Texas doctor’s plot to kill rival doctor in love triangle)

Later, when police questioned him, Shepard said his friend Dixon paid him three silver bars and gave a box of expensive Cuban cigars in return for killing Sonnier. Pawn shop records show that David Shepard had cashed silver bars the day after the murder.

July 16, 2012

Frank Sellers
Dr. Thomas Michael Dixon, also known as "Mike," was a plastic surgeon and had a spa in Amarillo, Texas.

Dixon is arrested in connection with the killing, the same day the Sonnier family held the funeral for their father in Shreveport, Louisiana.

Oct. 27, 2014

David Shepard’s own daughter, Haley Shepard, testified at Mike Dixon's second trial.

Dixon’s first trial begins with the prosecution using David Shepard, who had already given them a lengthy confession, as their star witness. Shepard, who is pictured above, had accepted a plea deal to testify against Dixon in exchange for pleading no contest to the charge of capital murder and avoiding the death penalty. He is currently serving a life sentence without the possibility of parole. As part of his plea deal with prosecutors, Shepard waived his right to appeal his conviction.

(MORE: Daughters of Texas love triangle murder-for-hire killer discuss dad's involvement)

But on the stand, Shepard surprises everyone and changes his story. He now claims that Dixon was not involved in the murder at all and that he acted alone. The defense argued that Dixon only asked Shepard to take photographs of Sonnier out with other women with the intent to show his ex-girlfriend, Richelle Shetina, but he never wanted Sonnier dead. They also said the silver bars Dixon gave to Shepard was part of a business investment for a company they were starting together.

The trial ends in a hung jury and the judge declares a mistrial.

October 2015

Lubbock Police Department
Dr. Thomas Michael Dixon faces trial in Texas, accused in the 2012 death of fellow doctor Joseph Sonnier.

Almost one year to the day later, testimony begins in Dixon’s re-trial for murder. The prosecution does not put David Shepard on the stand this time, but rather his house guest, Paul Reynolds, who recounts his story about staying with Shepard. But perhaps the most powerful testimony of all for the prosecution comes from David Shepard’s own daughter, Haley Shepard, who testifies that she believes her father lied on the stand in the first trial to protect his friend, Dixon.

Nov. 18, 2015

Dixon is found guilty on two counts of capital murder and is sentenced to life in prison without parole. His defense plans to appeal the verdict.

Dec. 13, 2018

The 7th District Court of Appeals in Amarillo, Texas, reverses Dixon’s conviction and grants him a new trial after his reviewing his appeal.

Jan. 17, 2019

Dixon’s bail is set at $2 million bond.

Jan. 28, 2019

Dixon is released from prison on a $2 million bond.

Feb. 11, 2019

Prosecutors file a petition to have Dixon’s conviction reinstated. If they prevail, Dixon will go back to prison. If they don’t, Dixon could face a third trial.