State prosecutors and defense attorneys offered wildly divergent theories of who killed Florida State University professor Dan Markel in 2014 during opening statements Thursday in the murder trial of two people accused in his death.

Dan Markel.

Georgia Cappleman, deputy assistant state attorney, told the jury of 10 women and two men assembled in a Tallahassee, Florida, courtroom that defendant Katherine Magbanua helped to broker a murder-for-hire and that co-defendant Sigfredo Garcia pulled the trigger, killing Markel in the driveway of his Tallahassee home while Garcia's friend Luis Rivera helped.

Behind the plot, the prosecutor asserted, are the mother and brother of Markel's ex-wife, Wendi Adelson, who was embroiled in a legal battle over where the couple's two-children would live. (No members of the Adelson family have been charged in connection with Markel's death.)

"Wendi Adelson had a problem, and that problem was Dan Markel," Cappleman said during her opening statement. "The solution to that problem was Magbanua, Rivera and Garcia."

Prosecutors said they believe that Wendi Adelson's brother, Charlie Adelson, and their mother, Donna Adelson, ordered the hit in order to help Wendi Adelson relocate to South Florida from Tallahassee with the couple's two sons to be closer to the Adelson family, which runs a dental clinic outside of Fort Lauderdale, Florida. Members of the Adelson family, as well Magbanua and Garcia, have steadfastly maintained that they had nothing to do with Markel's death.

Saam Zangeneh, who is representing Garcia, sought to discredit Rivera—the state's star witness—telling the jury that Garcia is a career criminal who would say anything to save himself.

Rivera is a leader of a Latin Kings gang in Miami and was already serving a 12-year federal prison sentence for racketeering when he and Garcia were arrested in 2016 for the Markel murder. Rivera pleaded guilty to second-degree murder and cooperated with prosecutors, implicating Magbanua and Garcia. He received a 7-year sentence to run concurrently with his earlier sentence.

"The only person who can put Sigfredo at the scene," Zangeneh told the jury, "is the guy who got the deal of a lifetime."

Zangeneh said that Rivera offered inconsistent stories about the murder that over time fit perfectly with the prosecution's theory of the case. The defense attorney offered an alternative theory of the killing: That Rivera was supplying drugs to Wendi Adelson's brother, Charlie Adelson, who hired him directly to kill Markel.

Rivera carried out the killing with the help of a Latin Kings associate in Tallahassee, Zangeneh told the jury. Moreover, Garcia disliked Charlie Adelson because he was dating Magbanua and would not have helped him. (Magbanua is Garcia's on-again-off again girlfriend and the mother of his two children.)

Magbanua's attorney, Tara Kawass, focused her opening statement on what she called holes in the prosecution's case against Magbanua and the state's selective approach to the evidence it will present at trial. The state has used Magbanua as a "pawn" in order to get to its ultimate target—Charlie Adelson—Kawass said. Her client's arrest and the three years since that she has spent in jail are an act of "prosecutorial desperation" in the absence of clear evidence tying her to the murder, Kawass told the jury.

Kawass offered an alternative explanation for the influx of cash that showed up in Magbanua's bank account in the months following the murder. The attorney said her client was working at clubs and doing promotional events for liquor brands, which were jobs that paid well, and in cash. Moreover, if Magbanua had received thousands of dollars from the Adelsons to set up a murder—as the prosecution alleges—it makes little sense that she would create an obvious paper trail by depositing it at the bank, Kawass continued. She also cast doubt on Rivera's credibility.

Judge James Hankinson of the Second Circuit Court of Florida is presiding over the trial. Jury selection in the case began Monday, and prosecutors expect to take four weeks to present their case.

Following the opening statements, the jury heard testimony from Markel's neighbor who called 911 after hearing shots fired and who found Markel slumped over in her car and covered in blood. In addition to a recording of that call, the jury heard testimony from the first Tallahassee police offer to arrive on the scene, as well as testimony from the man Markel was on the phone with at the time he was shot.

Markel and Wendi Adelson, also a lawyer, divorced in 2013 after seven years of marriage. The couple had joint custody of their two children but continued to wrangle in court over issues pertaining to the kids. At the time of his death, Markel had asked the court to prohibit Donna Adelson from having unsupervised visitation with the children on the grounds that she was making disparaging comments about him in their presence.

Following Markel's death, Wendi Adelson moved to South Florida with the children and changed their last name from Markel to Adelson.