Cell Phone Location Feature

Claim:   Enabling your cell phone's "Location On" feature can assist emergency services in reaching you.

PARTLY TRUE

Example:   [Collected on the Internet, June 2007]

Origins:   Cell phones have been used by law enforcement to locate people in missing persons cases and other criminal matters (for instance, it was

Kelsey Smith's cell phone that led police to her body), but cell phones have also been used to narrow the search for those who've had car accidents or have gotten lost in remote areas. They've even been used to find people whose loved ones had cause to conclude were intent upon harming themselves, as was the case in December 2006, when the pings from a Buffalo college student's cell phone led police to him in time to avert his suicide.

There's nothing magical to it: For mobile phones to work they have to be in regular contact with cell towers, so when handsets are on, they emit signals (called "pings") to nearby cell towers every few minutes to let the network know where they are. Most mobile phone companies keep records of calls to and from phones as well as a limited number of recent routine locater pings (sometimes just the last ping, sometimes up to 24 hours worth of them).

Although the location of a cellular handset can be traced via pings, there are two problems with using this method in emergency situations: One is that ping histories are part of customers' private phone records, and law enforcement agencies have to obtain subpoenas before gaining access to them. The other is that pings narrow the physical location of a phone only to the coverage region of a particular cell tower, an area that can encompass several square miles.

If an endangered cell phone user is able to place a call to 911, these stumbling blocks can be overcome because most wireless phones manufactured within the last few years are GPS-capable and can use signals from the federal government's Global Positioning System satellites to help estimate their locations. When the user of a wireless phone calls 911, the call is routed to a designated emergency call taker known as a Public Safety Answering Point (PSAP), usually local or county police, fire, or rescue services. If the handling PSAP has upgraded their phone system to Enhanced 911 (also known as E911) Phase II standards, they can use GPS information transmitted by a caller's cell phone to estimate the location of the caller to within about 50 to 300 meters (or better) and thereby guide them in getting emergency assistance to the proper area more quickly.

(All 911 calls already send information that enables PSAPs to automatically retrieve information such as the caller's phone number, the name and address associated with that phone number, and the general location of a wireless phone as calculated from tower sites, so even in areas where E911 Phase II technology has not yet been implemented, a 911 caller can generally be located even if he is unable to give his location to dispatchers.)

But what if, as suggested in the message quoted above, a cell phone user is injured, unconscious, or otherwise unable to use his cell phone to call 911? Can he still be quickly and accurately located through his cell phone, provided it's configured with the proper setting?

We've listed this item as "partly true" because we've queried several Verizon techs and received conflicting answers about the difference between the "E911 Only" to "Location On" settings. I finally talked to a Verizon public relations representative to try to get a definitive answer, and he asserted that (contrary to the claim made in the message quoted above) the "Location On" setting does not turn one's handset into a beacon that is traceable whenever the phone is turned on, even if the user does not make any calls. He said that no matter which setting is chosen, the user still has to place a call to 911 in order for emergency services to locate him or her, and that enabling the "Location On" option only allows authorized applications other than 911 services (such as Verizon's Navigator and Family Locator systems) to determine a handset's location.

(Keep in mind that all of this information is variable — whether this particular feature will work, and how well, depends upon factors such as the model of handset you use, which carrier provides your wireless service, what equipment is available to whomever you call, where you're calling from, and current atmospheric conditions.)

One good piece of general cell phone advice is that should you find yourself lost in a remote area, even if you cannot raise enough of a signal to make a call, at least power up your phone periodically and leave it on for a few minutes to enable it to send out pings to nearby towers. The record of those pings will help searchers figure out where to look for you.

Barbara "lost and foundling" Mikkelson

Additional information:

Government GPS / E911   (Verizon)

Last updated:   5 July 2011

Sources: