Because reporters want the public to understand how evidence is evaluated.

But by tonight there was no public evidence of a real breakthrough.

Little public evidence has emerged from Sudan for these claims.

To this date, no public evidence exists of such a missile series.

Their businesses, they say, are in jeopardy and there has been no public evidence why.

There is no public evidence to date that they played any direct role.

There is no public evidence that they, too, had everyone terrified about possible suicide.

There was no public evidence linking the attack to any cause, however.

Yet there is little public evidence that the parties have changed their positions.

Administration officials have thus far provided little detailed public evidence to support these claims.