The U.S. Ambassador-at-Large for International Religious Freedom did not show up for a congressional hearing Thursday on the issue.
Ambassador Suzan Johnson Cook was invited to testify, but she didn't come.
The State Department said she shouldn't have been asked to appear alongside witnesses from outside the government.
However, Utah Congressman Jason Chaffetz called her absence "inexcusable."
One religious freedom expert says Cook's absence shows that the White House puts a lower priority on religious rights than promoting gay marriage and contraceptives.