In certain contexts, such as a poisoning, some argue the bar must be raised to where the mere detection of a crime having been committed renders it imperfect.
They include Perfect Crime (play), Rope, Double Indemnity, Special 26 , Strangers on a Train, The Postman Always Rings Twice, Witness for the Prosecution, and Dial M for Murder.
Another possibility is that a crime might be committed in an area of high public traffic, where DNA from a wide variety of people is present, making the sifting of evidence akin to 'finding a needle in a haystack'.
Since there are no residents in the portion of Yellowstone National Park that lies within the state of Idaho, and since the entire park has been placed within the jurisdiction of the United States District Court for the District of Wyoming, there are no residents available to form a jury for crimes committed in this specific "Venn diagram" location.
[9] The infamous 1987 Opera House heist in India by a group of men impersonating CBI officers was described as a perfect crime.