DWI Detection and Standardized Field Sobriety Testing

DWI Detection and Standardized Field Sobriety Testing  

At the conclusion of this session, participants will be familiar with:

0.            •     Elements of DWI offenses

1.            •     Provisions of the implied consent law

2.            •     The relevance of chemical test evidence

3.            •     Precedents established through case law

In this session these four types of impaired driving laws are discussed in detail. The illustrations provided are drawn from the Uniform Vehicle Code. You are responsible for learning whether and how each law applies in your jurisdiction.

CONTENT SEGMENTS        LEARNING ACTIVITIES

A. Basic DWI Statute: Driving While   Instructor Led Presentations Under the Influence

B. Illegal Per Se Statute: Driving With a Prohibited Blood Alcohol Concentration

C. Implied Consent Law and Presumptions Reading Assignments

D. Preliminary Breath Testing

E. Case Law Review

Session 3 The Legal Environment

Notes:_______________________________________________

Basic DWI Statute It is unlawful for any person to operate or be in actual physical control of any vehicle within this state while under the influence of alcohol and/or any drug.

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A. Basic DWI Statute:  Driving While Under the Influence

A state's basic DWI statute may be subtitled Driving While Under the Influence, or something similar. Typically the statute describes the who, what, where and how of the offense in language.

For example:

It is unlawful for any person to operate or be in actual physical control of any vehicle within this state while under the influence of alcohol and/or any drug.

Session 3 The Legal Environment

Notes:_______________________________________________

DWI Violation Arrest

Probable Cause Person in question operating or in actual physical control of vehicle while under the influence:

0.            •     Alcohol

1.            •     Another drug

2.            •     Both

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Arrest

In order to arrest someone for a basic DWI violation, a law enforcement officer must have probable cause to believe that all elements of the offense are present. That is, the officer must believe that:

The person in question was operating or in actual physical control of a vehicle (truck, van, automobile, motorcycle, even bicycle, according to specific provisions in various states) while under the influence of alcohol, another drug, or both.

Session 3 The Legal Environment

Notes:_______________________________________________

Conviction

0.            •     Establish all four elements were present

1.            •     Operation

2.            •     Control

3.            •     Vehicle

4.            •     Impairment

5.            •     Criminal offense – establish facts                              “beyond a reasonable doubt”

6.            •     Infraction – standard of proof may be less

7.            •     Collect and document all evidence

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Conviction

In order to convict a person of DWI, it is necessary to establish that all four elements were present.

0.            •     Operation

1.            •     Control

2.            •     Vehicle

3.            •     Impairment

With regard to under the influence, courts have usually held that phrase to mean that the ability to operate a vehicle has been affected or impaired. To convict a person of a basic DWI violation, it is usually necessary to show that the person's capability of safely operating the vehicle has been impaired.  If DWI is a criminal offense, the facts must be established "beyond a reasonable doubt."  If DWI is an infraction, the standard of proof may be less.  In either case, it is the officer's responsibility to collect and thoroughly document all evidence.

Session 3 The Legal Environment

Notes:_______________________________________________

Illegal Per Se Statute It is unlawful for any person to:

0.            •     Operate or be in actual physical control

1.            •     Of any vehicle

2.            •     Within this state

3.            •     While having a BAC at or above the state’s level

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B. Illegal Per Se Statute:  Driving with a Prohibited Blood Alcohol Concentration

Description

Most states include in their DWI law or implied consent law a provision making it illegal to drive with a prescribed blood alcohol concentration (BAC). This provision, often called an illegal per se law, creates another alcohol-related driving offense, which is related to, but different from the basic DWI offense.  Following is a typical illegal per se provision:

It is unlawful for any person to:

0.            •     Operate or be in actual physical control

1.            •     Of any vehicle

2.            •     Within this state

3.            •     While having a blood alcohol concentration at or above state’s level.

Session 3 The Legal Environment

Notes:_______________________________________________

To Convict Illegal Per Se

0.            •     Establish BAC was at or above state level while operating vehicle in state

1.            •     Not necessary to establish impairment

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The illegal per se law makes it an offense in and of itself to drive while having a BAC at or above state’s level. To convict a driver of an illegal per se violation, it is sufficient to establish that their BAC was at or above state’s level while operating a vehicle in the state. It is not necessary to establish impairment.

Session 3 The Legal Environment

Illegal Per Se and DWI Each defines a separate offense:

0.            •     DWI – driving while under influence

1.            •     Chemical test is presumptive evidence

2.            •     Illegal Per Se – operate while having more than legal % of alcohol in blood or breath

3.            •     Chemical test is conclusive evidence

Notes:_______________________________________________

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The illegal per se law does not replace the basic DWI law.  Rather, the two work together.  Each defines a separate offense:

0.            •     The basic DWI law makes it an offense to drive while under the influence of alcohol and/or any drug.

1.            •     The illegal per se law makes it an offense to drive while having more than a certain percentage of alcohol in the blood or breath.

For the basic DWI offense, the chemical test result is presumptive evidence. For the illegal per se offense, the chemical test result is conclusive evidence.

Session 3 The Legal Environment

Notes:_______________________________________________

Illegal Per Se Purpose

0.            •     Aid in prosecution of DWI offenders

1.            •     Show the driver’s BAC was at or above state level

2.            •     Often required to secure conviction