But an underlying question remains about the self-policing system: Does it employ enough checks and balances to catch unscrupulous professionals, or even honest mistakes?

"First of all, they catch mistakes," said Mr. Friedman.

You also can magnify areas of the image during playback, giving you a chance to catch mistakes.

This system works reliably well for catching one-digit mistakes and digit swaps.

One of my duties is to watch everything in all departments of this fun house and catch mistakes before they happen.

It's much better if you catch mistakes before they do.

Some death-penalty advocates say that these figures show that the courts are diligent in catching mistakes.

If we are too stupid to catch the flaws in her story, she'll assume we won't catch later mistakes, either.

Spin one: the system works, because it catches mistakes.

Sure, listening to documents read aloud sometimes helps you catch mistakes a traditional proofreading pass might miss.