Anyone interested in justice  had to be disturbed by the Inquirer's in-depth report on "testilying," the term given to witnesses who lie under oath, sending innocent people to jail.

We know that eyewitness testimony is often wrong, even when witnesses are doing their best to accurately recall what they heard or saw. It is a different matter when the witness deliberately lies on the stand.

In the cases reported by the Inquirer, witnesses reversed their testimony, often years later.

The Inquirer reported judges are reluctant to accept recantations so long  after the fact unless they are supported by direct scientific evidence, such as DNA.

I asked Frank Farley, a Temple University psychologist with an interest in criminology, why that is so.

"The way we tend to view memory today is that it is dynamic, that it is ever-changing," he said. "It gets 'touched up' by subsequent experience."

In the face of this science, he said, "You can see why judges will say 'I can't deal with recantations of something 20 or 25 years ago.' Is it any more believable than the original testimony?"

Jennifer Creed Selber, who had headed the D.A.'s homicide unit, said she believes most people who recant do so because of fear of retaliation from defendants. That strikes me as something that's probably true in current cases, less so in those decades old.

Another disturbing element of the story were allegations by witnesses that police browbeat or threatened them into perjuring themselves.

Without question, we know that happens, but how can we tell if it happened in a particular case? How can we be sure they are not lying about this?

"This is one of the arguments for taping everything, all police interviews — everything should be on videotape," Farley said.

Aside from keeping the cops honest, videotaping would also help keep witnesses honest.

It might be harder for witnesses to come back years later claiming to have been forced to sign a false document when there is a video record of them calmly giving their testimony.

The Philadelphia Police Department's homicide unit has recorded interrogations of suspects since March 2014, using a machine that makes both audio and videotape recordings, Capt. James Clark told me.

Homicide "sometimes" tapes witnesses but Clark declined to offer "a hard and fast rule" as to when that is done.

Other police units couldn't be reached before press time.

To me, videotaping all interviews just makes sense. It's an idea that's clearly in the box.

Outside the box is my idea to invite suspects, witnesses, and victims to take polygraph tests. Yes, I know lie detector results are not admissible in court, but it might be a useful tool — and it would be voluntary.

I was a little surprised when Farley agreed with me.

First, he said, the results are not as bad as you think. He referenced a National Academy of Science study that said when the questions were tightly focused, polygraph results were good.

"I could see a person being asked" to take the test, Farley said, and "that might get them to answer more honestly."

If they are unwilling,  "you should be a bit more suspicious. Why be afraid of a lie detection test?" he asks.

In addition to taping interviews, and offering a polygraph test, I'd also have prosecutors take a few minutes to explain the consequences of perjury to anyone who would be called to testify.

These are common-sense steps to help insure more honest testimony and reduce the number of people wrongly incarcerated.

Isn't that a worthy goal?