From The Wall Street Journal's Review and Outlook blog:

Is it now so politically incorrect to oppose gay marriage that a white shoe law firm will throw over a client rather than defend a law signed by President Bill Clinton? Apparently so, after yesterday's show of invertebrate representation by King and Spalding, the giant Atlanta-based law firm.

...The likely story here is that King and Spalding began to fear a political backlash after activists at the Human Rights Campaign launched a campaign to "educate" (read: intimidate) the firm's clients about "King and Spalding's decision to promote discrimination." Clients include Coca-Cola and other Fortune 500 giants that prefer to avoid hot-button social issues.

That's fair enough, but once a firm takes on a client it is the firmest of legal obligations to see a case through save for a clear conflict of interest. To drop a case under political pressure is especially unethical. Imagine the outcry if a firm of similar standing stopped defending Guantanamo detainees?

Whatever one thinks of Doma, it passed both houses of Congress with huge majorities, and Vice President Joe Biden was among 85 Senators who voted "aye." The law defines marriage as between a man and a woman and says states aren't obliged to honor gay marriages recognized in other states.

Social mores have changed in 15 years, but not so much that gay marriage should be imposed by judicial fiat in a way that further inflames the culture war. The Human Rights Campaign has every right to challenge Doma in court, but it does itself no honor by trying to deny that same right to Doma's supporters by harassing their legal counsel. As for King and Spalding, better not turn your back on its lawyers in a firefight.