Cook County Sheriff Tom Dart is calling for abolishing the state’s cash-bond system, saying it’s unfair to low-level defendants who can’t afford to pay and puts society in danger when defendants with violent backgrounds have the money to post bail and are freed until trial.

Dart is believed to be the first elected official in Illinois to propose that the General Assembly scrap the system, said Cara Smith, his top policy official. It would require a change to Illinois’ bail statute — a daunting political challenge.

Currently, judges set bail for most people charged with crimes. Defendants typically need to pay 10 percent of that amount to obtain a bond to get out of jail before trial. In some cases, judges allow for a “recognizance bond,” in which no payment is required.

Dart is proposing a system in which a judge would decide whether a defendant should be released from jail until trial based solely on an intensive background investigation by the court’s staff.

“It would be similar to the investigation that is done on the federal level,” Smith said, adding that it would be more extensive that what is currently being done in Cook County.

Under current state law, cash bail is to ensure a defendant will show up for court, doesn’t pose a danger to the community and will comply with the conditions of bond. Judges should only set bail when they determine that no other conditions of release will meet those goals.

Dart is trying to find a way to keep people charged with minor crimes out of jail to make room for more violent defendants. Hundreds of people are in the jail because they can’t afford to pay small amounts of money to get out, sheriff’s officials have said.

“Today we have about 200 people who need $1,000 or less to post bond,” Smith said on Monday. “Many of them have been in jail for some time. For them, there is no way of avoiding the ‘oppressive’ nature of the bond that has been set.”

The law sets out factors for judges to weigh in setting bail, including the nature of the crime. Judges consider if the offense was violent, involved public corruption, harmed a public official, involved a weapon or was based on discrimination.

A judge must also evaluate the defendant’s employment history, family ties, mental condition and connection to the community to determine if the person is a risk to flee.

A judge can order drug testing and bar a defendant from associating with gangs while free on bond. The amount of bail is supposed to be “considerate of the financial ability of the accused” and not “oppressive.”

In addition to those factors, Cook County judges also receive a “public safety assessment” from court staffers with a score showing the risk of releasing a defendant on bond. The judges began getting those assessments in mid-2015. Critics, including the sheriff, have said judges don’t uniformly rely on those recommendations.

“It would be a much more thorough evaluation,” Smith said of what Dart is proposing for a no-cash system. “The goal would be to provide judges with much more information.”

A system that doesn’t rely on cash would be unusual, but not unheard of. Washington, D.C., has a no-cash system, and other states such as Colorado have considered it. There’s a bail-reform movement under way nationally.

According to The Washington Post, the court system in the nation’s capital typically releases about 90 percent of the people who have been arrested and held overnight. Those defendants simply promise to return to court and meet conditions like reporting for drug testing and checking in with a pretrial officer.

Nationally, about 47 percent of defendants with bails remain in jail awaiting trial, the Post reported.

Earlier this year, Dart pushed for another, less-drastic change in state law that would add sheriffs to the list of parties that can seek a reduction in bail. Those parties currently are judges, prosecutors and defense attorneys. The legislation is pending.

Dart and Cook County President Toni Preckwinkle, along with some county commissioners, have been pushing for judges to set lower bonds, expand electronic monitoring and order more no-cash recognizance bonds to allow defendants charged with nonviolent crimes to stay out of jail as they await trial.

The Cook County Board’s criminal-justice committee is scheduled to hold a hearing Thursday to explore the issue of monetary bonds.

“We’re confident the County Board hearing will begin to provide the roadmap for overhauling the system,” Smith said.