The stupidest criminals are the ones who think they're smart

Like Mr. Toxicology Guy, for instance:

Reno police arrested critical-care nurse Chaz Higgs on Friday in Hampton, Va., on a warrant charging him with first-degree murder in the death of his wife, former State Controller Kathy Augustine.

The arrest was made after police received a toxicology report from the FBI indicating the presence of succinylcholine, a powerful paralyzing drug, in her urine. The drug paralyzes muscles in the body within several minutes, including the muscles used for breathing, according to medical experts.

Police also used as evidence a phone call from a nurse who said Higgs allegedly told her on July 7 that accused Reno murder suspect Darren Mack had been "stupid" to have killed his wife the way he allegedly did, and said if he wanted to kill someone, he would use the undetectable drug succinylcholine.