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Felony Class and Mandatory Minimums

In Illinois, felonies are sorted into six classes based on severity. A felony’s class determines the range of sentences judges are legally permitted to dispense for an offense, outside a...

What are felony classes and mandatory minimums?

In Illinois, felonies are sorted into six classes based on severity. A felony’s class determines the range of sentences judges are legally permitted to dispense for an offense, outside a few offense-specific carveouts and enhancements.

This range includes the mandatory minimum, which is the shortest prison term a judge is legally able to sentence for a given crime.

The six classes used in Illinois, their current allowable sentencing range, and a few representative offenses are provided in Table 1.

Table 1. Sentencing range and example offenses for six felony classes in IL

ClassBase sentencing rangeExample offenses
First-degree murder (occasionally class "M")20 yrs. - LifeFirst-degree murder
Class X6 - 30 yrs.Predatory criminal sexual assault, armed robbery, home invasion, child sex trafficking, attempted first degree murder
Class 14 - 15 yrs.Aggravated robbery, second-degree murder, vehicular hijacking, production of child pornography
Class 23 - 7 yrs.Burglary, robbery, arson, witness harassment, kidnapping
Class 32 - 5 yrs.Aggravated battery, unlawful use of weapon, forgery, theft between $300 and $1,000
Class 41 - 3 yrs.Domestic battery, obstruction of justice, theft <$300

Misdemeanors are offenses less serious than a class 4 felony and fall into three classes (A, B, and C). Misdemeanors cannot be punished with prison time (though up to a year of jail time is permitted).

A few other factors to keep in mind: first, there isn’t always a one-to-one relation between criminal actions and charging offense: felonies are not necessarily written to be mutually exclusive, and often prosecutors have discretion to charge a person with offenses that differ in their sentencing range.

Second, other laws may require sentencing above the mandatory minimum (or put another way, raise the minimum). Firearm sentence enhancements, for instance, require judges to add between 15 and 25 years to the sentences of certain offenses. This means that adults who are convicted of first-degree murder with a firearm will receive a mandatory minimum sentence of 45 years, not 20. Other felonies have their own distinct sentencing rules: for instance, homicide with two or more victims must be punished by life without parole.

Many other states also organize felonies into classes in order to establish roughly standardized sentence ranges.

Why does it matter?

In Illinois, felony class determines the mandatory minimum a person must serve for a given offense. These mandatory minimums reduce judicial discretion and transfer power to prosecutors to influence sentencing outcomes through plea bargains (for more on that topic, check out any of these recent pieces on how plea bargains degrade justice).

In fact, between 2011 and 2017, over 80 percent of the roughly three thousand cases of armed robbery in Cook County resulted in plea bargains.

One way sentencing policies change in Illinois is through changes to the felony class system. This can happen either by changing an offense’s classification or by changing the range of possible sentences for an entire class.

Both of these changes were recommended in the final 2015 report of the Governor’s Commission as a way to reduce the state crisis of prison overcrowding. The Commission recommended a reduction in the minimum sentence for felonies on the order of 1 to 5 years for all felonies above class 4 (recommendation #13), as well as reductions in classification for a large number of controlled substance (recc. #15) and stolen motor vehicle offenses (recc. #17).

Notably, both these and the Commission’s other recommendations looked solely at reducing the minimum possible sentence, meaning judges retained their ability to dispense stricter sentences as they saw fit.

Neither proposal, however, was enacted into law in any substantive form.

Want to learn more?

This 2014 factsheet on criminal penalties—compiled by the Illinois General Assembly’s Legislative Research Unit—is a useful to have on hand.

A lot has been written about mandatory minimums. In their excellent brief, Families Against Mandatory Minimums clearly outlines the case against mandatory minimums and how they weaken our justice systems. Elsewhere, Marc Mauer of the Sentencing Project takes a close look at mandatory minimums and their impacts in the context of federal sentencing. To better understand the different types of arguments made for and against mandatory minimums, check out the summaries of oral and written testimony from a public 2010 hearing before the United States Sentencing Commission.

Linked Sources

Illinois General Assembly Legislative Research Unit. (2014). Penalties for Crimes in Illinois. Retrieved from

Families Against Mandatory Minimums. FAMM primer on mandatory sentences. Retrieved from

Heaton, R. et al. (2016, December). Final report of the Illinois State Commission on Criminal Justice and Sentencing Reform. Chicago, IL. Retrieved from

Mauer, M. (2010). Viewpoint: the impact of mandatory minimum penalties in federal sentencing. Judicature, 94(1). Retrieved from

Lynch, T. (2016, January 20). Americans are bargaining away their innocence. The Washington Post. Retrieved from

McArdle, M. (2017, September 26). Plea bargains are a travesty: there’s another way. Bloomberg. Retrieved from

United States Sentencing Commission. (2010, May 27). Summaries of the oral and written remarks of the witnesses United States Sentencing Commission public hearing. Washington, DC. Retrieved from

Yoffe, E. (2017, September). Innocence is irrelevant. The Atlantic. Retrieved from