The debate over how to stop the bloodshed in Chicago headed south in March as Illinois lawmakers took up a bill that would put more people with guns behind bars—for longer time.

There is a logic behind HB 2265, which was introduced by state Rep. Michael Zalewski, a Democrat from west suburban Riverside. The argument: that felons, gang members and just about anyone convicted of carrying a loaded gun might think twice if they knew that they’d face mandatory time behind bars. And if they didn’t, they’d do enough time—a minimum of about two and a half years—and stay off the streets. Presumably, that would help solve Chicago’s ongoing homicide crisis.

“What we have here in Chicago is a serious situation where the streets are not safe and the police are crying out for help,” Zalewski said.

If this new “war on guns” is starting to sound a lot like the “war on drugs,” well, that’s because it is. In fact, it has the potential to be a lot more expensive than recently passed tough-on-crime drug laws, shows a Chicago Reporter analysis of Cook County Clerk of the Circuit Court records.

Had the mandatory gun penalties under HB 2265 already been on the books, Illinois taxpayers would have been responsible for, at a minimum, more than $760 million in additional incarceration costs related to gun possession convictions between 2000 and 2011, the Reporter’s analysis found. That’s on top of the estimated $5.3 billion in incarceration costs stemming from all criminal cases originating in Chicago during that time.

The additional cost comes from the fact that roughly six out of every 10 people convicted of a felony gun crime in Cook County have been sentenced to time behind bars, the analysis shows. The other 10,130 defendants were sentenced to an alternative to prison like probation or boot camp—which would no longer be an option under Zalewski’s bill.

The Illinois Office of Budget and Management projects that the state would also have to spend an extra $263 million to build the prison space to accommodate the number of potential inmates.

“I’m not going to be disingenuous and suggest that the bill is not expensive,” Zalewski told me. “But if we say we can’t afford to protect public safety, we’re not doing our job.”

At press time in mid-April, the measure was passed out of the Illinois General Assembly’s House Judiciary Committee and is pending on the House floor.

Zalewski said he and his colleagues are debating whether they could relax some current mandatory prison offenses to free up inmate space for these gun-related crimes to blunt the cost.

Even if we could afford it, the question still remains: Would mandatory prison time be effective?

As I pondered this question, I was reminded of one of my old stories. A little more than two years ago, I dug into the court cases of youths who’d been convicted of adult felony gun crimes. I went into the project thinking that I’d be looking at some bad boys. It was a reasonable assumption, considering that young people have been involved in more than their fair share of Chicago’s homicides, whose number leads the nation by plenty.

I pulled the records to examine each of those convictions and, as I read through them, I quickly realized that I needed to throw all of my assumptions out the window. We ended up calling the piece, “Without a Smoking Gun,” with good reason.

Take Isaac Mobley’s case. At 16, he was trying to be a typical teenager. He played on the football team, made respectable grades and was on a drill team.

During his sophomore year, he transferred to an alternative high school because the trip to Hyde Park Academy High School was too dangerous. But he continued to have problems. Isaac decided to get a gun to protect himself. But he was caught with it at school, convicted of a gun-related felony and sentenced to mandatory time behind bars.

With what came across to me as a twinge of regret, Cook County Circuit Court Judge Vincent Gaughan said, “Mr. Mobley, it is just very unfortunate this stuff is happening.” Gaughan sentenced him to a year behind bars.

“I know the streets are dangerous,” Gaughan added. “You have to get that through your head, no matter how dangerous it is out there. You are going to be able to adapt without having the weapons. Otherwise, you are going to keep getting hurt.”

Isaac was eventually released into the same violent South Deering neighborhood. Within a year, he was gunned down while walking to a birthday party. His mother told me that police chalked up his death to being at the wrong place at the wrong time. It’s not an uncommon narrative.

Whether the stiffer sentence would have scared Isaac straight—we will never know.

is a staff reporter at The Chicago Reporter.