The Democratic National Convention was being held in Denver, and Barack Obama was to accept his party's presidential nomination before a crowd of 80,000 people that night.
The phone call was from one of Lindley's colleagues at Colorado's emergency preparedness agency. The deadly bacterium that causes tularemia — long feared as a possible biological weapon — had been detected at the convention site.
Should they order an evacuation, the state officials wondered? Send inspectors in moon suits? Distribute antibiotics? Delay or move Obama's speech?
Another question loomed: Could they trust the source of the alert, a billion-dollar government system for detecting biological attacks known as BioWatch?
Six tense hours later, Lindley and his colleagues had reached a verdict: false alarm.
BioWatch had failed — again.
President George W. Bush announced the system's deployment in his 2003 State of the Union address, saying it would "protect our people and our homeland." Since then, BioWatch air samplers have been installed inconspicuously at street level and atop buildings in cities across the country — ready, in theory, to detect pathogens that cause anthrax, tularemia, smallpox, plague and other deadly diseases.
But the system has not lived up to its billing. It has repeatedly cried wolf, producing dozens of false alarms in Los Angeles, Detroit, St. Louis, Phoenix, San Diego, the San Francisco Bay Area and elsewhere, a Los Angeles Times investigation found.
Worse, BioWatch cannot be counted on to detect a real attack, according to confidential government test results and computer modeling.
The false alarms have threatened to disrupt not only the 2008 Democratic convention, but also the 2004 and 2008 Super Bowls and the 2006 National League baseball playoffs. In 2005, a false alarm in Washington prompted officials to consider closing the National Mall.
Federal agencies documented 56 BioWatch false alarms — most of them never disclosed to the public — through 2008. More followed.
The ultimate verdict on BioWatch is that state and local health officials have shown no confidence in it. Not once have they ordered evacuations or distributed emergency medicines in response to a positive reading.
Federal officials have not established the cause of the false alarms, but scientists familiar with BioWatch say they appear to stem from its inability to distinguish between dangerous pathogens and closely related but nonlethal germs.
BioWatch has yet to face an actual biological attack. Field tests and computer modeling, however, suggest it would have difficulty detecting one.
In an attack by terrorists or a rogue state, disease organisms could well be widely dispersed, at concentrations too low to trigger BioWatch but high enough to infect thousands of people, according to scientists with knowledge of the test data who spoke on condition of anonymity.
Even in a massive release, air currents would scatter the germs in unpredictable ways. Huge numbers of air samplers would have to be deployed to reliably detect an attack in a given area, the scientists said.
Many who have worked with BioWatch — from the Army general who oversaw its initial deployment to state and local health officials who have seen its repeated failures up close — call it ill-conceived or unworkable.
"I can't find anyone in my peer group who believes in BioWatch," said Dr. Ned Calonge, chief medical officer for the Colorado Department of Public Health and Environment from 2002 to 2010.