Q. I am having a dispute with a local store regarding their return policy, worded as such: “[Retailers] will refund the purchase price of any previewed, defective or mislabeled products returned within 30 days, provided you have the original receipt.” The retailers claim that since the serial comma is not employed, “previewed” becomes a stipulation of both “defective” and “mislabeled.” Under their interpretation of the policy this is equivalent to saying “any previewed defective or previewed mislabeled products.” This is especially important to me, since I purchased a new, defective product from them.

A. Chalk one up for Chicago’s promotion of the serial comma! Although you must consult an attorney in order to learn the legal import of the phrasing in question, one can’t help but ask: if the retailers think that “any previewed, defective or mislabeled products” is equivalent to “any previewed defective or previewed mislabeled products,” would they also agree that “any mushroom, pepperoni or sausage pizza” is equivalent to “any mushroom pepperoni pizza or mushroom sausage pizza”? The retailers’ omission of commas in their interpretation (“previewed defective or previewed mislabeled”) is tantamount to admitting that the sentence was unclear as written. Finally, even if the retailers’ punctuation logic were technically correct (which it isn’t), they would be using the letter of the law to evade its spirit.