I'm not going to sit here and tell you Charles Zul would be a great Philly cop. All I know is that he was in the Police Explorers all through Father Judge, served as an Army Ranger in Iraq and Afghanistan, and upon his discharge aimed straight for law enforcement.

He's another candidate for the Philadelphia Police Department who was told he flubbed a mandatory lie-detector test.

He joins Greg Thomas, his colleague in the fugitive-nabbing warrant unit of the city court system, and guys like Dominic "Anthony" Mallamaci, who for six years has been walking the beat in Brooklyn for the New York City police but was told his test results alone doomed his candidacy to serve in his hometown.

Then there's Scott Jackson, who passed the critical questions in the polygraph given toward the end of the screening process, only to be told that his breathing was so over the top he was disqualified from joining the next class of recruits.

"I always breathe this way," says Jackson, a heating and air-conditioning salesman who had wanted to be a police officer since his best friend from Archbishop Ryan, Officer John Pawlowski, was shot and killed in the line of duty in 2009.

"A couple months after he died, I decided that this is what I wanted to do."

I have no idea what sort of officers any of them would make, but I'm not sure the Philadelphia Police Department does either.

Because none of them passed their polygraph tests, their candidacies are over. For now.

The rules might be changing.

When I wrote about Thomas last month, police officials said they had decided that if a potential recruit failed two or more of four key questions posed by outside polygraphers to uncover deception, the candidates were automatically disqualified, with no appeal.

A whopping 63 percent of those tested by the contractor failed, Deputy Commissioner Patricia Giorgio-Fox says.

Since then, Giorgio-Fox says, the department has heard from several hundred people wanting a second look, and later this fall, after the department fills its second class of recruits, she and other police brass will reevaluate the methodology. That's reason for hope.

The department reinstituted the lie-detector tests this year to address integrity issues in the department, she said.

Critics, such as George W. Maschke, who maintains the antipolygraph.org site, says there's no scientific basis for the test. "Many honest applicants are ending up being wrongly accused of deception."

One researcher in favor of using lie-detector tests to screen candidates, Mark Handler, says that they are excellent tools, but only as good as the questions posed, and that the results alone should not be used to disqualify anyone from the force.

Handler is research director of the American Association of Police Polygraphers. He was the lead author of a 2009 paper in the Journal of Police and Criminal Psychology that determined hiring decisions based just on polygraph results were hard to justify.

Instead, he and his coauthors wrote, police should use a "whole person" approach, in which the test is weighed against everything else known about a potential officer. The accuracy of those tests, they say, is in the mid-80 percent range.

Even the model policy written by the American Polygraph Association says flatly: "Polygraph test results should never be used as the sole basis for the selection or rejection of a law enforcement or public-service applicant."

That message has made its way to Philadelphia. Giorgio-Fox said she was inclined to agree that one test should not end a person's candidacy.

"I totally agree this should be a tool, an important tool, and weighed heavily," she said, "but it should in fact not be used to hire or fire." She invited all who have failed the test to reapply after the fall class enters the academy.

Sounds like progress.

or @danielrubin on Twitter. Read his blog at philly.com/blinq.