I'm with Dick on this. Sending it halfway around the world, the chain of custody would be questioned, the ability of the defendant to review the test methods and interview the experts that performed the tests, etc., would be impractical. If it were a London proofed gun and the litigation was for enormous money, that could pay for these expenses,... maybe. The tip of a finger on the average Joe, using a gun never proofed in London and maybe not worth the proof fees...I don't think so. If it were Brad Pitt's finger tip, it might happen, but Brad Pitt wouldn't be caught with a Tri-Star.