Aaron Cohen was a popular and gregarious triathlete who spent the last minutes of his life riding his bicycle alongside Biscayne Bay, talking about his beloved wife and two children.

Michele Traverso is a 26-year-old student with a rare genetic disorder who battled substance abuse.

The details of their lives played out in court Wednesday in a gripping sentencing hearing that culminated in a surprise decision: Traverso will serve just 364 days in jail for driving away after his car plowed into Cohen on the Rickenbacker Causeway last February.

The sentence, handed down by Miami-Dade Circuit Judge William Thomas, angered scores of Cohen’s relatives, supporters, and cycling enthusiasts who gathered in court to pay tribute to the 35-year-old car dealer.

“It’s a terrible injustice,” Stephen Cohen, a lawyer and Aaron’s father, said. “This was the wrong kind of message to send to the public.”

Meanwhile, Traverso delivered an emotional hug to his lawyer, Ramon de la Cabada, who argued passionately that the slight, bespectacled young man needed to stay out of state prison to avoid complications from his potentially fatal immunological disorder.

Traverso has already served almost a year in jail, which will not count toward the new sentence. Thomas also ordered Traverso to serve two years of house arrest. The judge’s sentence also means Traverso will stay in a Miami-Dade jail, not a state prison.

Traverso faced a minimum of 22.6 months in prison and up to 30 years behind bars.

The fatality, and a similar hit-and-run wreck in 2010, renewed calls for increased safety for cyclists and joggers on the popular causeway. Fellow cyclists staged a memorial ride and erected a billboard overlooking Interstate 95 in Cohen’s honor.

“This was not something I did lightly. I did what I thought was most appropriate,” Thomas told the Cohen family after choking up himself, recalling the recent death of a family member.

According to prosecutors, Traverso struck Cohen and cycling partner Enda Walsh as the pair rode near the crest of the bridge. Traverso did not call 911, but instead called his lawyer. He surrendered to police the next evening, a delay his lawyer blamed on his own scheduling conflicts and police bureaucracy.

Investigators suspected that Traverso had been drinking after finding receipts from a Coconut Grove bar for three gin drinks.

But with no proof Traverso actually consumed the drinks — no blood testing could be done because of the delay in surrendering — prosecutors could not charge him with DUI manslaughter.

Surveillance video from his family’s Key Biscayne condo showed his father covering up the Honda with a tarp.

At the time of the crash, Traverso had been enrolled in a drug-court program after a cocaine-possession arrest. He tested positive for marijuana and also showed up drunk to a court session, admitting he had been drinking the previous night, prosecutor Jane Anderson told the judge.

On Wednesday, relatives remembered Cohen, 35, as a dynamic personality who grew up in Chicago, speed-skated, played polo, and fished with his father on trips. His younger sister, Sabrina Cohen, tearfully recalled her brother driving her across country to attend college.

For his mother, Cohen — a business-development manager at Esserman Automotive Group — constantly posted photos of his two young children on Facebook.