Referring to Clinton's support for partially repealing DOMA, Pepperdine law professor Douglas Kmiec said, "Clinton's position is the more logically consistent position: If an individual is in a state-recognized same-sex marriage, they will not [under Clinton's approach] suffer any different treatment [from heterosexual couples] under existing federal law."
"Whereas Obama's position," Kmiec continued, "not only gives an endorsement to same-sex marriage in the context of federal law, it also makes it less likely -- not more likely -- that the states which favor traditional marriage will be displaced in their judgment."
Kmiec, an outspoken conservative who served as constitutional legal counsel for Presidents Ronald Reagan and George H.W. Bush, believes Obama's approach is more likely invite judicial activism because the repeal of DOMA will make the recognition of same-sex marriage more of a "judicial question" than if Congress had clearly spoken by leaving DOMA intact.
Tribe rejects Kmiec's warning about Obama's approach by arguing that a court that feels compelled to recognize a same-sex marriage conducted in another state can do so even with DOMA in place.
Referring to D.O.M.A.'s relationship to the Constitution's Full Faith and Credit Clause, Tribe said, "a state that fits professor Kmiec's hypothetical would be a state that would not be influenced by Congress anyway because an act of Congress is subordinate to the Constitution."
View the ad that Tribe made for Obama's campaign here.
ABC News' Nik Bonovich contributed to this report