Dear Rich: I am producing a documentary and I videotaped a couple of 30-second commercials off the TV -- it is evident from the way I framed the image that the ads are showing on a TV -- in order to make a point about the ad's message. I realize that, as you say, fair use is a defense, not a right, but am wondering if this qualifies as fair use. I'm so glad you asked. Fair use is an affirmative defense. Fair use is not always fair. Stop, you're both right. The problem in answering fair use questions is that there are no bright lines... you can only look at how past cases have been decided, review the four fair use factors and make a guess. The Dear Rich staff believes that adding one or two 30-second commercials to a one-hour documentary has a good chance of qualifying as a fair use and if you want to lower the odds of getting hassled (1) use only a portion of the commercial, (2) make it clear that your use of the ad is conveying a message (not selling the product), (3) avoid commercials that feature celebrities, and (4) avoid commercials that feature pop tunes. Even then, if the other side is well-heeled and driving a steamroller, you'll have a problem -- for example, if the corporate sponsor of the commercial finds out about your use and believes it will harm the business, you can expect a C&D letter in your inbox.