Portage police Detective Capt. Terry Swickard has a lot of confidence in the department's computer voice stress analyzer.
The results of the high-tech lie detector test are not admissible in court, he said, but they have helped guide investigations toward convictions and the release of innocent suspects.
As a result, Swickard was not at all swayed by news of a Pentagon-sponsored study that concluded the technology performs at chance level and is ineffective in detecting the presence of deception or stress.
The study verified earlier findings, which had led the U.S. Department of Defense to no longer use voice stress analyzers, according to a spokesperson, who said it is policy not to be identified by name.
The computer voice stress analyzer, which is among two types of units evaluated in the University of Florida study, is used by police departments in Porter and Lake counties.
The maker of the units, National Institute for Truth Verification of West Palm Beach, Fla., said in a prepared statement that this and earlier studies are flawed because they are unable to produce the same type of jeopardy experienced by those undergoing the voice test in real-life situations.
The authors of the study said they prepared for this concern by factoring in the lack of "real-world" stress as part of their evaluation.
The National Institute for Truth Verification said 1,500 law enforcement agencies have relied on the units over the past 18 years and that an independent survey of agencies reported an accuracy rate of over 91 percent.
Porter Police Chief James Spanier, who was undergoing training with the computer voice stress analyzer at the time of the Sept. 11 terrorist attacks, said there must be some consequence for lying in order for the tests to be effective.
He also said the results are only as good as the questions asked.
Defense attorney Larry Rogers said he has been aware of the criticism of the tests for several years and is not surprised by the defensive responses from police.
If police were to admit the faults with the technology, they would be opening themselves up to liability and objections over the waste of tax dollars, he said.
Each computer voice stress analyzer unit costs $10,000 and six-days of training runs $1,440 per person, said Bill Endler, director of NITV. Endler is a retired police chief from Syracuse, Ind., and has worked at other departments around the state.
Rogers said he advises all his clients to exercise their right to refuse the voice stress test.
"You might as well use a Ouija board," he said.
Michael Higgins, spokesman for the Lake County Sheriff's Department, said the Pentagon study will have no impact on the department, which has five certified voice stress operators.