Family and friends of Florida State University law professor Dan Markel have waited a long time for answers in his 2014 execution-style shooting

Family, friends and colleagues of Dan Markel, a popular Florida State University law professor, have waited a long time for answers in his 2014 execution-style shooting.

Investigators suggest it was tied to his ex-wife’s family amidst a “bitter divorce” and child custody disagreement.

Markel, 41, died a day after he was shot point-blank in the head while parked in his Honda Accord in the garage of his suburban Tallahassee, Florida, home about 11 a.m. on July 18, 2014.

Two named suspects are proclaiming their innocence in the alleged murder-for-hire plot and are headed to trial — while a third has pleaded guilty and is working with police.

Authorities are still trying to link Markel’s killing to the family of his ex-wife, fellow Florida State law professor Wendi Adelson, according to testimony and court documents.

Lawyers for Adelson, her brother and their parents dismiss that allegation as “fanciful fiction” and say none of the Adelsons have been charged because they have no connection to the killing.

Here are five things to know about the unfolding case:

Dan Markel
| Credit: Florida State University College of Law

1. Ex-Wife Introduced the Idea of Her Family’s Involvement

Markel and Adelson married with bright promise.

Their 2006 wedding announcement was published in The New York Times. Adelson, then a third-year law student at the University of Miami, moved to join the Toronto-born Markel in Tallahassee, where he taught criminal law at FSU. Eventually she would also join the law faculty, and the couple would have two sons, Ben and Lincoln.

But after six years of marriage, in September 2012, “Markel reportedly returned home from a business trip to find his family gone, a majority of the contents of the house missing and the paperwork for dissolution of marriage displayed on his bed,” according to a criminal affidavit in the case made public in June.

When he learned that Adelson had moved with their two boys to her parents’ home in South Florida, Markel protested until she returned and a legal case ensued.

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The divorce was granted in July 2013, without a trial. But a judge denied Adelson’s motion to relocate the children.

“E-mail evidence indicates Wendi’s parents, especially her mother, wanted Wendi to coerce Markel into allowing the relocation,” according to the affidavit. “Additionally, Wendi’s brother, Charles Adelson [Charlie], reportedly did not like Markel and did not get along with him.”

Markel and Adelson were living apart in Tallahassee on the day he was shot.

After police picked up Adelson to inform and question her about the shooting, “She had said that someone may have done this for her benefit without her knowledge,” Tallahassee police detective Craig Isom testified during a hearing in December.

“She made the statement that her brother had joked the previous summer about hiring a hit man but instead decided to buy her a television,” Isom said.

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Wendi Adelson
| Credit: Florida State University College of Law

2. Police: Family Conflict Allegedly ‘Motive for This Murder’

Markel’s affection for his boys was on view to all who saw their crayon drawings on display in his office and home, where he hosted small gatherings of students for lively academic debates preceded by home-cooked meals.

“He had a dozen nicknames and terms of endearment for those he loved, most especially for Benjamin and Lincoln — who were Ben and Lincy, Ben-Ben and Lincabus, Cubby and Dewey, the little bears, the delicious ones, little love balls of light, his wonder balls, and the magical ones,” wrote a longtime friend and former Harvard classmate in an online tribute.

“They were indeed magical to him, for he was in awe of them in every moment.”

Markel also was protective of them: At the time he was shot, he waiting for a hearing to be scheduled on a motion to potentially restrict access to the boys by Wendi’s mother, Donna, whom he claimed had “made disparaging remarks about him to his sons.”

Coupled with the pressure placed on Wendi to move closer to her family, police outlined their theory in the May 2016 affidavit: “Investigators believe motive for this murder stemmed from the desperate desire of the Adelson family to relocate Wendi and the children to South Florida, along with the pending court hearing that might have impacted their access to the grandchildren.”

Attorneys for Wendi and Charlie and their parents, Donna and Harvey, rebuked that in a joint statement, saying: “There has been a lot of unsupported speculation that the Adelsons had something to do with the murder. That speculation is categorically false.

“To be clear, none of the Adelsons — Wendi, her brother Charlie, or their parents Donna and Harvey — had anything to do with Dan’s murder.”

3. Records Connect Murder Suspects to Ex-Wife’s Family

Police fairly quickly said Markel had been targeted. But for months they released only a single clue, describing a gray or silver Prius seen in the area of the shooting.

The first arrest came in May 2016, quickly followed by a second — and with those arrests came the allegation that Charlie Adelson was connected to the case.

Suspects Sigfredo Garcia and Luis Rivera, who were both charged with first-degree murder, matched descriptions of individuals sought by police. They had rented a Prius that was colored “Silver Pine Mica” to travel from South Florida, according to tracking information that placed the pair in Tallahassee on the day of the shooting.

Police also revealed in May that Charlie was allegedly “involved in a personal relationship” with the mother of Garcia’s two children, Katherine Magbanua, who would eventually also be charged with first-degree murder.

Two weeks before Markel was killed, Magbanua and Charlie had been together in Key West, Florida, according to phone records, Detective Isom testified in December.

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Sigfredo Garcia
| Credit: Broward County Sheriff's Office HOGP

Cell phone data, ATM records and a Tallahassee eyewitness tied Garcia and Rivera to the case, police alleged. And Garcia’s first call after the murder was to Magbanua, they said.

As the two men drove back to South Florida from Tallahassee on the day of the shooting, Garcia told Magbanua over the phone, “It’s done,” Isom testified, adding: “Once he had uttered the words, ‘It’s done,’ she replied with, ‘I know.’ ”

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Luis Rivera
| Credit: Federal Bureau of Prisons

Rivera, 33, pleaded guilty to second-degree murder in a plea deal, and was sentenced to serve seven years in prison. His penalty was added to a 12-year sentence he was already serving on an unrelated racketeering charge, for which he had been arrested and convicted after the Markel shooting.

Garcia, 34, and Magbanua, 32, have both pleaded not guilty to their murder charges.

4. Police Claim Money Also Connects Magbanua to the Adelsons

Rivera told police that he, Garcia and Magbanua split a $100,000 payment for the hit.

In his testimony, detective Isom described an “obvious spike” in Magbanua’s income after the shooting, and he said she spent $4,400 in cash for breast enhancement surgery three months after the shooting.

Isom also claimed Magbanua received $10,500 in payments from the Adelson family’s dental practice, operated by Charlie and his father, where she was counted as an employee despite months of law enforcement surveillance that never saw her enter or exit the office.

(In September, another police affidavit alleged that Charlie along with Garcia, Rivera and Magbanua were “responsible for the murder of Dan Markel.” The affidavit also claimed Rivera and Garcia purchased several cars and motorcycles after the murder.)

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Katherine Magbanua
| Credit: Broward County Sheriff's Office

Prosecutors have since made a plea to launch a hearing to determine who is paying for Magbanua’s private defense.

“If the money is traced back to the Adelsons, it would really give them something,” a source close to the investigation tells PEOPLE.

Magbanua’s attorney, Christopher DeCoste, tells PEOPLE in an email that the prosecution “is more interested in proving their theory than finding the truth.”

“The case against Katie is nothing more than the prosecution speculating as to how the murder went down and supported only by the unreliable word of a lifelong gangster,” he wrote, referring to Rivera’s statements to police.

“That evidence was recently put to the test,” DeCoste wrote, “The cracks are massive and the prosecution is now desperate, willing to do anything, attack anyone, to hold it together.”

He continued, “They’re wrong on their theory of the murder, just like they’re wrong on their theory of who’s paying for Katie’s defense, which is her immediate family. They’ve gone into their savings, into their retirement accounts, causing financial hardships, all in order to protect Katie from a wrongful conviction at the hands of an overzealous prosecution.”

Magbanua’s next court hearing is scheduled for May. Garcia’s murder trial is set for November.

5. Ex-Wife Discussed the Suspicion About Her — ‘Because It’s Usually the Ex-Wife’

Wendi Adelson has not publicly addressed the allegations made against her family. But in 2015, she enrolled in a writing class and discussed Markel’s murder in her essays and a related podcast that grew out of the class.

Recalling the news of his shooting, she wrote and recited about that day, “I only found out this information when the police picked me up from a lunch date I was having with two girlfriends and insisted that I come with them back to the station, and then interrogated me for eight straight hours. Because it’s usually the ex-wife.”

(Such a comment reflects Wendi’s characteristic wry irony, an acquaintance of hers told PEOPLE.)

“He died violently and young, and likely at the hands of a professional killer, and the media had a field day in response,” Wendi said. “I turned on the TV to find photos of my children with Nancy Grace, George Stephanopoulos saying my name in reference to our ‘acrimonious divorce,’ and a picture my friend took when I was her maid of honor showed as evidence of why I should be treated as a murder suspect and not the mother of two fatherless boys.”

She explained to the podcast host her reasons for sharing her personal writings.

“I think for me, a lot of the additional pain I felt, on top of the murder and everything associated with it, was it felt unfair that I couldn’t at least tell my own story, that the story got told for me,” Wendi said. “So I think there was an aspect of empowerment, of being able to say, ‘No, this is my side of the story.’ ”

She also discussed the loss she still felt after the death of her ex, while watching her young boys at play.

“An older woman sitting next to me commented on how adorable my boys are and asked, ‘What does your husband do?’ I hate this question,” she said. “I haven’t yet said, ‘He doesn’t do much because he’s dead.’ But I think it sometimes.”

“I find when I tell people that my children’s father died, they feel sad,” she continued. “But when they ask the follow-up questions and find out we weren’t married, they seem to feel better.”

“I don’t,” she said.

• With reporting by STEVE MILLER