April 1, 2013

Blind spots in electronic monitoring of sex offenders

California corrections officials find that the Global Positioning System isn't always wired for reliability.

Paige St. John / Los Angeles Times

(Continued from page 1)

click image to enlarge

Parole agent Steve Nakamura uses a flashlight to inspect a GPS locator worn by a sex-offender parolee in Rio Linda, Calif. California had to replace thousands of the devices recently because they proved easy to thwart.

The Associated Press

When statewide monitoring began in 2008, California split the work between a division of 3M Co. and Houston-based Satellite Tracking of People, or STOP. The 3M device was used to track some 4,000 parolees in all but six Southern California counties. STOP had the rest of the state, including Los Angeles.

When California later sought to switch to a single provider, 3M came in with the low bid.

For a week in late 2011, parole agents abused both companies' devices. They were dropped 4 feet onto concrete, wrapped in foil to block their signals and submerged as long as three hours in a swimming pool. Testers allowed batteries to run dead, cut ankle straps and traveled into areas beyond the reach of satellite and cellular phone signals.

Without revealing full details of the tests, officials declared 3M's devices so faulty that the state rejected the company's bid. When 3M protested, Milano began a second round of tests that she said showed 3M's ankle monitors posed a public safety emergency.

The state claimed that 3M's devices failed to meet 46 of 102 field-tested standards for the equipment, although the company said a fourth of the failures occurred because the state had not provided the phone numbers needed to send automated text alerts.

One agent who participated in the tests, Denise LeBard, said in a court statement that 3M's ankle monitors were "inundated with defects."

Among the problems: 3M's devices failed to collect a GPS location every minute, phone in that information every 10 minutes and forward a text message to a parole agent if a problem was detected. Without revealing how well STOP performed, the state said 3M collected only 45 percent of the possible GPS points.

Testers also were able to fool 3M's GPS devices by wrapping monitors in foil, something that triggers an alarm on STOP's device because it has a metal detector.

Engineers and experts within 3M's electronic monitoring division vigorously dispute the alleged faults. They accused California of rigging the tests to steer the contract to STOP.

"This is one agency's testing," said Steve Chapin, vice president of government relations for 3M's electronic monitoring division. "We have the most widely used system in the world. It's been proven time and time and time again to be very safe and reliable."


In a heavily censored declaration, Milano also disclosed a test in which the 3M ankle monitor failed to "wake" from a battery-saving sleep mode, creating uncertainty about an offender's location. She cited the rest mode issue, along with what she described as a four-year history of other problems, as grounds to order parole agents in April 2012 to immediately replace every state-issued 3M monitor in California with one from STOP.

3M argued in court that GPS signals are blocked so frequently that no ankle monitor can really distinguish between accidental and deliberate interference. Its device triggers tamper alerts only when both GPS and cell signals are lost for more than two minutes, a feature even the company said is not foolproof.

"Neither 3M nor STOP can produce a device that will read the offender's mind to determine his or her intent, so the devices can only 'assume' that a tamper is intentional," 3M said.

A Sacramento County judge in February ruled that Milano had violated state contract laws, but he upheld her decision that 3M failed state standards.

Industry experts say the issues raised with 3M are not unique to that company, and problems with the state's monitoring system probably still exist.

Peggy Conway, editor of the Journal of Offender Monitoring, said every electronic monitoring system has blind spots and weaknesses.

"There is no one perfect product," she said.


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