The Police Chief, the Professional Voice of Law Enforcement
Advanced Search
September 2016HomeSite MapContact UsFAQsSubscribe/Renew/UpdateIACP

Current Issue
Search Archives
Web-Only Articles
About Police Chief
Law Enforcement Jobs
buyers Your Oppinion

Back to Archives | Back to November 2008 Contents 

Halting Auto Theft in Its Tracks: OnStar’s Stolen Vehicle Slowdown Protocol

By George Baker, Public Policy Manager, OnStar by GM

ith every additional mile per hour the speedometer clocks a vehicle involved in a high-speed chase, the likelihood of a positive outcome diminishes. According to U.S. National Highway Traffic Safety Administration statistics, about 30,000 police chases occur yearly, and approximately 300 deaths result.

A new technology from OnStar by GM aims to combat these grim statistics. The technology, known as Stolen Vehicle Slowdown (SVS), enables OnStar advisers, working in tandem with law enforcement agencies, to slow down stolen vehicles remotely, assisting thereby in the prevention of high-speed chases.

SVS is an enhancement to OnStar’s Stolen Vehicle Assistance, a service that uses Global Positioning System (GPS) satellite technology to pinpoint the location of a stolen vehicle. Once law enforcement officers have established a clear line of sight with the stolen vehicle, an OnStar adviser will remotely flash the stolen vehicle’s lights to verify for authorities that they have the correct vehicle in their view. After law enforcement officials have determined that conditions are safe and that police backup is on hand if needed, they can request a slowdown.

OnStar will then send a signal to the vehicle that interacts with its power train system to ignore the throttle input. Within seconds, the vehicle will begin to decelerate to an idle speed. During these slowdowns, drivers have use of all the vehicles’ other systems (such as steering and brakes), so they are able to control the vehicles and safely pull them over to the side of the road.

IACP Involvement

The IACP in particular and the law enforcement community in general have played crucial roles in the development of protocols for SVS deployment since the initial demonstration of the technology in September 2007. As a matter of fact, in October 2007 OnStar briefed the IACP’s Highway Safety Committee on the technology. Key representatives from the Michigan State Police were part of an end-to-end test of SVS protocols during a live demonstration of a slowdown.

On the heels of this demonstration, OnStar conducted a thorough review of SVS processes and protocols with local police and dispatch officials. Representatives from the IACP, the National Emergency Number Association, the National Sheriffs’ Association, and the Association of Public-Safety Communications Officials from both Canada and the United States attended this two-day review in Detroit.

Each of these review processes encouraged open dialogue during which SVS protocols and procedures could be refined, before a formal presentation and demonstration was made to the IACP’s Highway Safety Committee in June 2008.

“We’ve received a showing of support from the IACP for this new technology and assistance in developing the process,” noted Bill Ball, OnStar’s vice president for public policy. “An important IACP suggestion was to develop a reenactment detailing the Stolen Vehicle Slowdown procedures, which we’ve added to our new public safety training video.”

Subscriber Interest in SVS

Initial research indicates that 95 percent of OnStar subscribers want the SVS capability with their cars and trucks. Even so, OnStar subscribers have the choice of opting out of the SVS capability at any time by contacting OnStar. Discontinuing the SVS mode will not affect any of the other OnStar services a subscriber already has.

Stolen Vehicle Slowdown Process

  • An OnStar subscriber reports a vehicle
    as stolen to police.

  • The subscriber calls OnStar to request
    Stolen Vehicle Assistance.

  • OnStar uses real-time GPS technology
    to pinpoint the exact location of the
    stolen vehicle, provides this information
    to the appropriate law enforcement
    agency, and indicates if SVS is available
    on that vehicle.

  • Once officers have established a clear
    line of sight with the stolen vehicle and
    have confirmed it is safe to slow the vehicle
    down, they can request that OnStar
    initiate a slowdown.

  • OnStar sends a remote signal to eliminate
    accelerator response, which slows the
    vehicle gradually to an idle speed.

  • At the request of the responding agency,
    OnStar sends another signal to return the
    vehicle to normal operation.

“We’re certainly encouraged by OnStar’s approach and appreciated being asked to provide input during the development of the SVS protocols,” said Earl M. Sweeney, assistant commissioner of the New Hampshire Department of Safety and chair of the IACP’s Highway Safety Committee. “Law enforcement has been asking for something like this for years,” he continued, “because many current intervention methods are becoming less effective, and pursuits still remain dangerous to everyone involved.” Other public safety organizations, such as the International Association of Fire Chiefs (IAFC) and the Fraternal Order of Police (FOP), have joined the IACP in expressing their support for this technology.

“We see this technology as an opportunity to improve the likelihood of a positive outcome for all involved in such dangerous road situations,” noted Chief Steven P. Westermann, IAFC president.

Chief David Hiller, FOP national vice president, added, “We look forward to having technologies like Stolen Vehicle Slowdown available to aid our officers in apprehending suspected car thieves and keeping our officers, highways, and citizens safe.”

For more information on SVS or other OnStar services, readers can visit or send an e-mail message to



From The Police Chief, vol. LXXV, no. 11, November 2008. Copyright held by the International Association of Chiefs of Police, 515 North Washington Street, Alexandria, VA 22314 USA.

The official publication of the International Association of Chiefs of Police.
The online version of the Police Chief Magazine is possible through a grant from the IACP Foundation. To learn more about the IACP Foundation, click here.

All contents Copyright © 2003 - International Association of Chiefs of Police. All Rights Reserved.
Copyright and Trademark Notice | Member and Non-Member Supplied Information | Links Policy

44 Canal Center Plaza, Suite 200, Alexandria, VA USA 22314 phone: 703.836.6767 or 1.800.THE IACP fax: 703.836.4543

Created by Matrix Group International, Inc.®