CPD CPD Traffic Enforcement & Vehicle Operations

Question 1

Under Illinois law, what is the legal blood alcohol concentration (BAC) limit for non-commercial drivers aged 21 and older?

Accepted Answer

0.08%

Answer

Illinois law (625 ILCS 5/11-501) sets the BAC limit at 0.08% for drivers 21 and older.

Question 2

When conducting a traffic stop, how should a CPD officer position their patrol vehicle relative to the stopped vehicle?

Accepted Answer

10–15 feet behind and offset to the left

Answer

Offsetting the patrol vehicle to the left creates a safety buffer and provides cover from passing traffic.

Question 3

What does the Horizontal Gaze Nystagmus (HGN) field sobriety test detect?

Accepted Answer

Involuntary eye jerking caused by alcohol impairment

Answer

HGN measures the involuntary jerking of the eyes that becomes exaggerated when a person is impaired by alcohol.

Question 4

Under Illinois's Implied Consent Law, what consequence does a driver face for refusing a chemical test?

Accepted Answer

Automatic statutory summary suspension of driving privileges

Answer

Illinois Implied Consent Law mandates automatic license suspension for any driver who refuses a lawfully requested chemical test.

Question 5

What is the first action a CPD officer should take when a vehicle fails to yield during a traffic stop attempt?

Accepted Answer

Notify dispatch of the vehicle description and direction of travel

Answer

Immediately notifying dispatch ensures supervisory awareness and enables other units to assist before a pursuit is authorized.

CPD - Chicago Police Department Practice Test