Ever since the New Orleans tow-truck company owner Cardell Hayes shot the retired local pro-football champion Will Smith to death and wounded the former athlete’s wife on a city street late on the night of 9 April 2016, people on all sides of the case have made it as complicated as possible in their fight for what they consider to be justice.

It is a case that has gripped south-eastern Louisiana – where football players are huge celebrities – and also involved dark, if unsupported, allegations of another deep south staple: police corruption. Competing theories and narratives have vied for supremacy, with almost as many different ideas of what happened as people willing to voice them.

But all the evidence available at two separate trials – including one that concluded early Saturday with a second manslaughter conviction for Hayes – points to a simpler, senseless tragedy that maybe could have only happened in a country plagued with an excess of short tempers, easily accessible guns and laws that make people believe it’s relatively safe in many situations, legally speaking, to fire those weapons.

Perhaps the best guess at what happened on the night Smith’s and Hayes’s lives collided with deadly consequences is what follows, based on accounts from key observers who initially had no idea precisely who was involved and therefore had no loyalty to either the shooter or the slain.

Smith spent the day attending a street festival as well as dining and drinking with his wife, Racquel, and friends in New Orleans, home to his family and the NFL’s Saints, a team that won its first and so far only Super Bowl title with his defensive help just six years earlier.

The 34-year-old Smith was driving Racquel and two of their companions in his Mercedes-Benz SUV to a hotel bar to continue the revelry when he lightly struck the back of a Hummer being driven by Hayes, who had braked as he approached traffic at a red light. With a friend in the passenger seat, and having no idea who hit his rear bumper, Hayes pulled over – but then began pursuing Smith after he drove away.

Hayes then hit the rear of Smith’s SUV, and the six people in both cars got out, leading to a confrontation that by all accounts was heated.

At that point, a patron at a nearby bar heard one of the men near the crash warn that he had a gun. A second man answered that he had a gun, too, before he was shot in the back and killed.

Investigators later arrived to find Smith with eight bullet wounds – seven to his back – slumped over his front seat, inches away from a pistol that was tucked in between the seat and the center console. Racquel, who recounted being at her husband’s side during his encounter with Hayes, was shot twice in one of her legs and badly wounded.

An off-duty police officer who was on a date at the same bar as the other patron later said he approached the scene after hearing the gunfire, and he was told by Hayes that he used a pistol he had on him to shoot Smith after hearing that Smith was going back for his own gun.

That off-duty officer reported Hayes telling him: “What was I supposed to do?” There was also a recording of a 911 call that night which captured Hayes in the background saying he had shot a man who announced his intention of getting a gun from his car.

Smith’s funeral service was held days later in a theater full of mourners, after a viewing open to the public at the Saints’ practice facility.

Despite his claims that he killed Smith legally in self-defense, Hayes was charged with murder, twice facing judgment in the killing.

The prosecution and the defense have since spent countless hours arguing that one man was clearly to blame and the other was not in the shooting that led to Smith’s death, his wife’s injuries and Hayes’s criminal trials. The local and national news media’s duty to vet all aspects of the case in a collective quest for the truth about what occurred that night in a way has added to the obfuscation.

But the truth is neither prosecutors’ nor defense attorneys’ versions of Smith’s fatal shooting are supported by the neutral, credible accounts relayed in the immediate aftermath.

State prosecutors maintained at both trials that Racquel Smith talked her husband into walking away from the face-off that erupted after the second car collision. She did that because Hayes – a former semi-professional football player – was, improbably, even more physically imposing than her husband. She also testified that she implored her husband to remember their three children, who were being babysat at home, and said the violence “is not worth it”.

Then, she says, Hayes deliberately pumped two bullets into one of her legs and shot her husband dead – in cold blood, and without provocation, before he was taunted with the phrase: “Look at you now.”

“My worst nightmare happened for no reason,” Racquel Smith has said under oath.

Her account was twice bolstered with testimony from her husband’s former Saints teammate and fellow Super Bowl XLIV champion Pierre Thomas, who has described riding in a separate car ahead of the second collision and getting out to see Smith’s killing.

Hayes, when first tried, testified and suggested Smith actually got a gun other than the one found in his center console, fired at Hayes first and accidentally shot Racquel in the process. Hayes has testified it was only then that he fired at Smith, whose blood-alcohol level was later determined to be three times over the legal driving limit.

At one point, Hayes’s legal team publicly suggested that a retired police captain who was friends with Smith stormed on to the scene and – to burnish memories of the fallen ex-football pro – whisked that gun away before investigators could recover it.

Media briefly seized on the insinuation for a couple of reasons. That retired captain had dined with Smith shortly before the player’s death. And, in a chilling coincidence, Hayes’s father had tried to stab that policeman before being shot dead by other officers in the months after Hurricane Katrina struck New Orleans 11 years earlier, according to authorities. Police said the elder Hayes had a mental health emergency on the day officers shot him dead.

The Hayes legal team’s “corrupt cop” angle relied on the well-documented history of a New Orleans police department that had violated the public’s civil rights so many times that it entered into an agreement with the federal government in 2012 to implement what was then an unprecedented number of agency-wide reforms. But that theory suffered a blow after prosecutors established that the officer alleged to have engaged in a cover-up for the sake of Smith’s legacy was waiting for Smith miles away at the hotel bar where his group was headed before he was killed – though the defendant’s attorneys never ruled out that another officer who resembled the accused retired captain could have taken the gun fired at Hayes.

All told, what neutral bystanders saw and heard conflicted markedly with Racquel Smith’s testimony that her husband was calmly walking away from escalating violence when he was callously murdered and she was shot in the leg.

And Hayes’s version of events wasn’t supported either by those same recollections or ballistics evidence recovered from the scene, which showed only he shot a gun. Even testimony from Hayes’s friend and passenger – who drew his own gun but did not fire it the night of Smith’s death – failed to say that Smith had ever fired at Hayes.

Prosecutors always have the obligation to prove their assertions definitively while the defense can succeed simply by introducing reasonable doubt about the state’s case in jurors’ minds. Nonetheless, it’s likely that the gaps between the impartial observers and their partial counterparts explain the mixed outcome of Hayes’s first trial.

Some of the Saints’ most renowned figures at the time – whom New Orleanians treated like royalty – were in attendance throughout the trial to support Smith’s family. Yet jurors did not hand up the ideal outcome desired by those dignitaries, many of whom had won New Orleans’s only major professional sports championship alongside Smith.

Jurors acquitted Hayes of intentionally ramming Smith’s car in the moments before the shooting, which prosecutors had wanted to prove he had done to establish that he was the aggressor in the deadly showdown that ensued. Jurors also rejected that Hayes had willfully murdered Smith or attempted to murder Racquel, which would have landed him a mandatory sentence of life in prison.

The jury instead found Hayes guilty of manslaughter and attempted manslaughter, finding that he unintentionally but still illicitly killed Will Smith and wounded his wife in the heat of an argument.

Hayes – who has spoken about cheering Smith and his Saints compatriots as they pursued on-field glory as well as dreaming of being able to join them in the trenches – received a 25-year prison sentence that would take him away from the son he was raising.

But only 10 of 12 jurors voted to convict Hayes of the lesser charges at the end of that week-long trial, arguably the highest profile case at New Orleans’s criminal courthouse since the 1969 acquittal of a local businessman charged with helping plot the assassination of President John F Kennedy.

And when the US supreme court later ruled that such non-unanimous jury verdicts were unconstitutional, the stage was set for Hayes to be released from prison in 2021 and retried on the reduced charges of which he had once been convicted.

Hayes did not testify at his second trial, where his courtroom supporters included renowned bounce musician Big Freedia, a relative. The second jury never heard Hayes’s unsubstantiated tale that he gave from the witness box the first time around.

But Hayes’s choice against taking the witness stand in his retrial made little difference for him. Though jurors made the puzzling decision to acquit him of Racquel Smith’s attempted manslaughter, they found him guilty of manslaughter in Will Smith’s shooting death – unanimously this time.

That verdict once again leaves Hayes faced with serving a lengthy prison sentence.

Ultimately, nothing in the second trial – which ran for five days beginning on 22 January – substantially changed the picture that the first trial painted of Smith’s final night.

Three men in two separate cars that crashed had three pistols among them. With tempers flaring over what could have been handled with misdemeanor citations, insurance companies and civil litigation if necessary, two of the men declared to each other that they had guns with them.

One father was shot dead moments after that dual declaration. The other at least survived and, at 36, has lived longer than did the man whose life he ended. But he already spent some of his prime years in prison, is returning there for a long time, and will be best known to many in his city as simply a killer.

As Thomas reportedly put it while on the witness stand more recently: “This whole situation sucks … This whole situation is unfortunate. It could have played out different.”