When it comes to sex, a lot of what we think of as being "normal" today was illegal and carried serious punishments in the not-too-distant past. For instance, federal law in the United States (specifically, the Comstock Law) used to prohibit the distribution of pornography, contraceptive devices (including pamphlets and information about birth control), and sex toys through the mail. This law was in effect for decades, and it had enormous implications for people's sex lives, not to mention their health. However, this is just one of many examples of how sex laws have been out of synch with people's sexual needs and desires.

For a closer look at the interaction between sex and the law in recent years, check out the segment below from NPR's Fresh Air in which host Terry Gross interviews Eric Berkowitz, author of the new book The Boundaries of Desire: A Century of Good Sex, Bad Laws, and Changing Identities. Berkowitz offers an eye-opening look at a wide range of sex laws, including those that used to permit spousal rape, as well as those that banned homosexual behavior. It's a fascinating discussion, and if you're interested in learning more about this topic, his book is well worth a read.