On Friday night, a 15-year-old was arrested — along with two teen accomplices — for bumping and carjacking a retired Chicago Police officer who was unloading his luggage at a Streeterville hotel.

The teen was back on the street by Sunday, only to be arrested for yet another carjacking.

Exasperated by the epidemic of carjackings and the number of repeat offenders, Mayor Rahm Emanuel is working with four state lawmakers from Chicago to draft legislation aimed at stiffening penalties against carjackers.

The bill, still in the drafting stages, is expected to be co-sponsored in the Illinois House by State Reps. Jaime Andrade Jr., Arthur Turner and Marcus C. Evans Jr. The Senate sponsor is expected to be Sen. Antonio Munoz.

“When somebody is stopped today [after] police pursuit of a stolen car, what often people are saying is, `I borrowed it from somebody else.’ Or, `I got it from somebody. I don’t know his name.’ Or they say nothing,” said Walter Katz, the mayor’s deputy chief of staff for public safety.

“The evidence is really clear based upon the person’s actions that they had a clear intent to have this stolen car. That’s what we’re trying to go after.”

Katz noted that the current law requires proof that the person in possession of the stolen car “knew it was stolen.”

“We’re trying to address that issue by providing more tools for prosecution to hold such folks accountable,” he said.

Emanuel’s communications director Adam Collins said the new carjacking task force tailor-made to confront the problem will have trouble making a “big dent…if criminals know the criminal justice system doesn’t take carjacking seriously.”

Citing the Friday night carjacking and Sunday’s re-arrest for the same crime, Collins wrote, “That’s nuts, and the only way to fix it is by strengthening the state laws.”

On Sunday, Police Supt. Eddie Johnson made a similar point after announcing the FBI, ATF, State Police, and local and federal prosecutors would join Chicago Police on a new team to combat carjackings.

“Juveniles are committing these crimes far more than they used to. You can’t just give them a slap on the wrist because when we do that, the message that we send is that we’re not serious about holding them accountable,” Johnson said.

“People do it because they use those vehicles to commit other crimes like drive-by shootings or smash-and-grabs. . . . We also know that some of them are committed just for the thrill of doing it, and the reason we know that is because we’ll recover that same vehicle four or five blocks away.”

There were 663 carjackings in 2016 and nearly 1,000 last year. And the problem seems to be getting worse.

During the first month of 2018 there were 86 carjackings — a 19 percent increase over January 2017.

The brazenness of carjackings in the downtown area — often after motorists are bumped from behind and get out of their cars to assess the damage — have created unflattering headlines with the potential to discourage tourists from visiting Chicago and suburbanites from coming downtown to enjoy the city’s nightlife.

On Friday, the teenaged carjackers just happened to choose the wrong victim.

A 54-year-old retired Chicago police officer was unloading his luggage outside a Streetervlle hotel when a carjacker got in the running car and drove off.

The car got stuck in traffic, giving the retired officer an opportunity to catch up to the vehicle and detain the driver, a 15-year-old boy. The victim got an assist from a man in a wheelchair who blocked the path of the fleeing car, witnesses said.

The teen was arrested and charged along with two other boys. The alleged accomplices were 14 and 17, police said.