document if the file space that that document occupied had not been overwritten. >> when this crime was committed in 1988, there were no computer programs that could reassemble documents that had been deleted. so al johnson and his team had to do something that had never been done before. they had to do the analysis manually. >> it's a painstaking process that took approximately 33 days to look at two, 20-megabyte hard drives. >> a computer is about as secure as a wet paper bag. it never throws data away. >> they found bits and pieces of a document kopenheffer had deleted called "the plan." it listed all of the steps necessary to carry out sally weiner's kidnapping and murder. >> we were able to recover 80% of the plan back off of the hard drives. 20% of that had been overwritten or altered and to a point where we couldn't recover the data.