Authors:

The information gained from these techniques was valuable in some instances, but there is no way of knowing whether the same information could have been obtained through other means.

"Banned Techniques Yielded ‘High Value Information,’ Memo Says". www.nytimes.com. April 21, 2009.
The information gained from these techniques was valuable in some instances, but there is no way of knowing whether the same information could have been obtained through other means.