A person I know cheated through most of their science classes while an undergrad. He literally had someone else take the exams for him, write his reports, and do most of his homework. He then took his stellar GPA and not so stellar GRE score and got admitted to a not so great PhD program.
His new girlfriend at grad school wrote a lot of his papers. He ingratiated himself with the head of the department – he is a schmooze king. He gained favor by doing physical work that very few of the other grad students would do. His doctoral thesis was weak and the defense round wasn't difficult. He was awarded his PhD. Mind you, he still can't explain to me nearly anything about basic chemistry, organic chemistry or biochemistry concepts. I'm talking like sn1, sn2, benzene rings, buffers, etc...
He now has a job with a pharmaceutical company doing anything but real science. He's basically a pharmaceutical rep out selling drugs to various physicians in a territory.
Do I tell his employer? Do I tell the university? Do I let it go? I have no way to prove anything. I'm sure none of those guys that took his tests for him will come forward and tell the truth. He has gotten away with fraud.