Ignition Interlock Requirement

SQ Attorneys Ignition Interlock Requirement

Ignition Interlock Device Requirement  (“IID”) in DUI/ DUI Related Cases

State of Washington Ignition Interlock Requirement laws (RCW 46.20.720) require the installation of an Ignition Interlock (“IID“) on an individual’s vehicle when convicted of DUI in Washington State.  The amount of time the IID is required can be up to ten years; the amount of time a person is required to have an IID is based upon on a number of things, to include:

  • The number of DUI convictions the person has on his/her criminal record;
  • The blood alcohol concentration of the person;
  • Whether the DUI conviction involved a minor (under 16 years of age) in the car; and
  • Whether there was an IID in place during any license suspension period.

To determine how long one may need an IID on his/her vehicle after a Washington DUI conviction, it is recommended that you consult with the experienced Seattle DUI attorney.  SQ Attorneys is well versed in, and intricately familiar with, the DUI and Ignition Interlock Requirement laws of Washington State, and can make a huge difference in the outcome of any DUI related charge in Western Washington.

What is, and how does, the IID Work?

The IID is attached to a vehicle’s ignition and the driver must blow into the device to start the vehicle and, at times, to keep it running.  The IID makes use of a fuel-cell sensor to detect alcohol content in an individual’s breath.  It is designed to measure the blood alcohol level of a driver. If a breath sample registers over the acceptable level, the vehicle will not start, or if in motion it will turn off.

Potential Problems in Using Ignition Interlock Devices
Although designed to prevent drunk driving, and to protect the public at large, there are some potential consequences related to possessing an IID:

  • False Positives – the IID can potentially detect mouth alcohol created by such things as mouthwash. Moreover, certain foods contain yeast and sugar and this too can possibly cause positive results. A driver who is required to have an IID on his/her car must be extremely aware of what he/she eats or drinks so as to prevent false positives.
  • Malfunctions – nothing is infallible – accuracy and reliability are not guaranteed. Like any machine malfunctions are bound to occur; IID’s use complex fuel-cell technology.
  • Shared Vehicle – if the convicted person is sharing the vehicle with another person, the other person will need to use the ignition interlock device as well; the device is not individual sensitive.

Costs associated with IID’s are just under $100 per month, currently.


10.0Gregory Wayne Schwesinger
10.0Saad Qamer Qadri