Science Doesn't Lie

"Science doesn't lie," the medical examiner stated firmly, pointing at the corpse under the harsh morgue lights. "Based on the tissue decomposition and complete lack of chemical preservatives, the time of death was exactly one week ago." The detective scowled and slammed a thick file onto the stainless steel table. "That's impossible. The victim went missing two years ago, and DNA confirms this is definitely our guy." The examiner stared at the body in absolute disbelief. How could a man who died two years ago only show one week's worth of decay?