Mealey's (July 28, 2015, 7:59 AM EDT) -- DETROIT — A mechanical engineer can testify as an expert witness that the design of a portable tree-climbing ladder caused the injuries of a hunter who fell from the ladder because the expert is qualified and his opinions are reliable and relevant, a Michigan federal judge held July 23 (Patrick Valente, et al. v. Oak Leaf Outdoors, Inc., No. 14-12892, E.D. Mich.; 2015 U.S. Dist. LEXIS 95819)....