It is the driver's responsibility to be aware of the posted speed limit. The
maximum speed limit is 65 miles per hour on rural interstates, 55 miles per
hour on interstate highways near or in major cities and on other highways, and
30 miles per hour in an urban area unless some other speed restriction is established.
The maximum speed limit outside an urban district for a house car, camper, private
living coach, vehicle licensed as a recreational vehicle, any vehicle towing
any other vehicle, and vehicles of the second division designed or used for
the carrying of a gross weight of 8,001 pounds or more, is 65 miles per hour.
No vehicle may be driven upon any highway of Illinois at a speed which is greater
than is reasonable and proper with regard to traffic conditions and the use of
the highway, or endangers the safety of any person or property. The fact that
the speed of a vehicle does not exceed the applicable maximum speed limit does
not relieve the driver from the duty to decrease speed when approaching and
crossing an intersection, when approaching and going around a curve, when
approaching a hill crest, when traveling upon any narrow or winding roadway, or
when special hazards exist with respect to pedestrians or other traffic or by
reason of weather or highway conditions. Speed must be decreased as necessary to
avoid colliding with any person or vehicle on or entering the highway.
For speeding not more than 20 miles per hour over the posted speed limit and other traffic
offenses, as provided for under Supreme Court Rule #526, a person shall post
bail in the amount of $120 in one of the following ways: (1) posting $120 cash bail; or (2) by depositing, in lieu of such amount, an approved bond certificate; or (3) by depositing, in lieu of such
amount, a current Illinois driver’s license.
Bail for speeding more than 20 miles per hour over the posted limit, but not more than 30 miles
per hour over the posted limit, is $140 cash or in lieu of such amount, his/her
current Illinois driver's license or an approved bond certificate. Bail for
speeding more than 30 miles per hour over the posted speed limit is $160 cash or in lieu of such amount, his/her driver's license or an approved bond
certificate. Bail for failure to use safety belts is $60 cash or in lieu of such amount, his/her current Illinois driver's license or an approved bond
The Illinois State Police utilizes hand-held radar, moving
radar, pacing, laser speed measurement devices, photo speed
enforcement and air speed measurement to determine the speed
The first mechanical means to measure vehicle speed was the
stop watch. As early as 1906 the courts accepted that the time it took a vehicle
to travel between two points could be converted to vehicle speed. Using the
speedometer and keeping pace with another vehicle has been utilized since 1916.
The Illinois State Police started using radar in 1956. Radar uses radio
waves that bounce off moving vehicles. In 1959 the state police started using
the stop watch method of measuring vehicle speeds from airplanes. The state
police now operate a fleet of fixed-wing aircraft for speed enforcement.
In the 1970's, hand-held radar was made available to most troopers. In
the 1980's, moving radar enabled troopers to clock the speed of vehicles
approaching from the front or rear while driving down the highway. In the
1990's, laser speed measuring devices were introduced. The laser devices use
laser light beams that bounce off a moving vehicle.
Approximately 32 percent of all fatal crashes are speed-related.
Speed-related crashes most often involve only a single vehicle.
Speed was found to be one of the most prevalent driver-error-related causes contributing to fatal crashes in 1992.
The number of vehicles operating at higher speeds on 65 mile per hour
interstate highways has increased. This has resulted in:
increased chance of a collision due to increased speed variance.
greater risk of fatality resulting from higher crash impact speeds.
Of all drivers involved in speed-related fatal crashes in 1992, about 42
percent were under the influence of alcohol. Less than 29 percent of drivers
in all fatal crashes were under the influence of alcohol.
Source: Fatal Alcohol Reporting
Systems 1992 Report to Congress - Effects of the 65 mph Speed Limit
How To Avoid Being A Speed Related Crash
Obey the posted speed limit on all roads.
Reduce your speed when road conditions are less than ideal.
Stay alert to changing road conditions and to the vehicles around you.
Go with the flow. Travel at the same pace as other traffic, staying within
the speed limit. If most other vehicles are speeding, stay to the right.
At night and in other low visibility conditions, reduce speed and increase
your following distance. Make certain you are seen by other drivers -- use
Maintain your vehicle and tires in safe working order.
When following another vehicle, follow at a distance of at least two
seconds. When the rear bumper of the vehicle ahead of you passes a stationary
object, count "one thousand and one, one thousand and two." As you finish
counting, your front bumper should reach the same point.
Always wear your safety belt. In a sudden swerve or other emergency
maneuver, it will keep you behind the wheel where you can maintain control.
Never drink and drive.
Know you limitations and adjust to them. Drivers under age 25 tend to be
in good physical shape, but also tend to lack experience and mature judgement.
Drivers over 65 have experience, but may have diminished physical and sensory
capabilities. The ability to see well at night decreases with age, becoming
noticeable after about age 40.