Does Olive Oil Need Kosher Certification?

When you read this article, http://www.newyorker.com/reporting/2007/08/13/070813fa_fact_mueller which lists numerous cases of fraud involving the sale of a multitude of oils under the guise of Virgin or Extra Virgin Olive Oil, the answer should be obvious. (Update:  The article turned into a book- Extra virginity : the sublime and scandalous world of olive oil  by Tom Mueller.  I recently saw another article on the subject here.) We know that there is no legal meaning for "Virgin" olive oil; it is as meaningless as "pure", and anyone can put it on their label even if it is utterly without basis in fact. And let us also get past the fact that "virgin," "extra virgin," and "extra extra virgin," are not only no more meaningful than "yummy!", and that this kind of marketing hyperbole is just silly, unless you are comparing seminaries in Israel. But assuming that the fear of legal action for libel and slander is keeping the New Yorker honest, anyone using an olive oil without a hechsher is practically guaranteeing that he is consuming Mystery Oil, an oil that could be anything, from hazelnut oil to sunflower oil to soy bean oil to canola oil. Sometimes, you also get a little beta carotene for color. In fact, brazen fraud and misrepresentation appear to be so widespread that one has to wonder whether can even rely on a hechsher! Krinos, found to be distributing soy bean oil mislabeled as olive oil, claimed they had been fooled by their suppliers. How can a kashrus organization combat such skilled and powerful forces in the industry unless they follow the product from tree to bottle, as if the chumra of nis'alem would apply?

It seems that just as most hechsherim involving products made in China are worthless, (imagine how laughable it is to claim to guarantee kashrus in a plant where you don’t understand the language, come only three or four times a year, where the criminal misrepresentation is pervasive, skilled, and abetted by the government, where they know you’re coming as soon as you buy an airline ticket, and who successfully bamboozled Mattel and Purina and Nissan,) so, too, hechsherim on olive oil should be viewed with suspicion.

Imagine how perplexing it was for me to learn that one of our universally respected Poskim and Roshei Yeshiva holds, lehalacha and lema'aseh, that no hechsher is necessary for olive oil! I spoke to him about this, and he told me to look at the Aruch Hashulchon YD 114:17-18.

To avoid causing confusion for people who are unfamiliar with the nuanced style of the Aruch Hashulchon, I will not write what he says. But the tone and content of his words, and the relevance to this issue, is remarkable. Once again, evidence for the proposition that daas baal habayis (me) hepech midaas Torah (the Rosh Yeshiva).
From the Mahari Weil, שו"ת מהר"י ווייל סוף סימן קמ"ו, הובא בסמ"ע סימן ג' ס"ק י"ג
פסקי בעלי בתים ופסקי לומדים שני הפכים הם
I believe the Sma, elsewhere in Choshen Mishpat, uses the expression with Seichel Baalei Batim.

So, as far as the title of this post, the answer is that "Der shaileh fahngt zach nisht ohn."

The bottom line is: the halacha does not require a hechsher for olive oil.  The Aruch Hashulchan strongly defends the application of this rule even in the face of claims of changing times.  I understand that it is worth being meikil in order to maintain the concept of emunah in Chazal.  But this baal habayis remains troubled by reliance on this halacha.