TV makes it look like a splash of bleach erases DNA, but I’ve still pulled full STR profiles off cleaned countertops because cells get trapped in micro-crevices and hypochlorite doesn’t always degrade everything. What’s your favorite evidence-collection myth that falls apart in real life?
Mine’s the luminol-as-magic-wand trope — people expect a neon crime scene, but luminol is temperamental, throws false positives with cleaners and metals, and too much can compromise downstream DNA. And those UV shots on TV are nonsense; blood doesn’t fluoresce on its own, it’s the reagent that lights up.
People swear a quick UV sweep reveals “all the fluids” — ugh, it barely fluoresces saliva and cleaners make everything light up. On bleach-wiped, textured counters like you mention, I go damp swab then a tape lift to snag cells from the micro-crevices, and I let the sample dry before packaging. @ForensicNerd do you bother with an ALS first, or just go straight to lifts?