You can tell from his body movement that he was very nervous, couldnt have his arms and legs holding still and walking all over the place, + he was looking way too often at the officer. I also noticed him taking lots of sips from his water bottle, when you are very nervous your tongue and mouth are dry as a desert (i also get this sometimes when im doing a play for theatre lol f ing annoying!) Someone who would be innocent would be more looking around because he would feel less safe once he heard there was an escaped prisoner around... I have to admit his story was very well made up and he stayed as calm as he could be. Dont forget he just improvised all of this on the spot knowing his enemy is right in front of him! my nerves wouldve just killed me if i was him right there lol.