luwndes county sheriff office. >> we believe somebody core resulted this video because it doesn't make sense. >> reporter: who is right? to find out, we took our copy of the video provided to cnn by the attorney for the sheriff's office to an expert. we brought the hard drive 2300 miles to spokane, washington to deliver it to the leading expert grant fredericks. he's a former police officer, a consultant for the u.s. department of justice and a construct instructor at the fbi academy. we're here to get an answer. has the surveillance video been altered? >> they are not original and investigators should not rely on. >> reporter: cnn hired his company, forensic video solutions to analyze the surveillance video. >> the first thing that the attorneys and the family were concerned about, they didn't see