Mr. Clinton was asked what he had learned from the last year of investigation and impeachment.

Over a year of investigation, the myriad connections became clear.

But after four and a half years of intensive investigation, there are no simple answers in sight.

But after years of investigation, engineers concluded that they had been wrong.

The legislation followed several years of investigation and exploration by a special committee.

After a year of investigation, no evidence could be found to confirm their deaths.

Following three years of "investigation and demonstration," the leadership decided to proceed with nuclear power development.

Justice Department officials, who have been under intense pressure to produce results after more than a year of investigation, were delighted with today's developments.

So what facts have we established after a year of investigation?

Even after six years of investigation, the information remains maddeningly incomplete.