It was clear he required proof of any statement, no matter what its source.

If anyone requires proof before acting, we can show it to them.

Under such circumstances, one does not require proof in order to exploit the information.

The Council may still require proof of any savings that are held below this amount.

To establish standing, the courts have required proof of three elements.

I'm taken with religious folks who argue that you not only can, but should believe without requiring proof.

To prove a crime, she said, would have required proof of criminal intent.

And to be sure, these kinds of cases are difficult to bring because they require proof that someone knowingly did something wrong.

Most jurisdictions around the world still require such proof of fault.

Before making any changes, Facebook requires proof that the user has died.