(CNN) -- When Bill Clinton takes the podium at the Democratic National Convention Wednesday evening his wife, Secretary of State Hillary Clinton, will be half a world away -- literally -- meeting with the leaders of the tiny nation of East Timor.
Hillary Clinton, who hasn't missed a Democratic convention in four decades, is on an 11-day swing through the Asia-Pacific region, visiting a number of counties, including China and Indonesia, and standing in for President Barack Obama at the Asia-Pacific Economic Cooperation forum later this week in Russia. Obama bowed out because of the election campaign.
Some Clinton-watchers see an ulterior motive, concluding that the secretary, who waged a hard-fought campaign against Barack Obama for the Democratic nomination in 2008, still bears a grudge.
But the two have worked closely since then and, what's more, there's a less adversarial explanation for her absence from the convention: legally, she can't be there.
Federal law -- the Hatch Act of 1939, amended by Congress in 1993 -- specifically prohibits secretaries of state from attending political conventions, and the State Department's own ethics guidelines also rule out political activity.
A senior administration official, speaking on background because the official is not authorized to speak on the record, told CNN, "The law carved out the State Department as having a unique position in the government in that foreign policy, by its nature, must remain nonpartisan/apolitical."
"So State Department officials -- specifically those who are presidential appointees confirmed by the Senate (i.e. the secretary) -- are far more restricted than, say, someone who works at the Education Department."
When Condoleezza Rice was President George W. Bush's Secretary of State, she did not attend the Republican National Convention. Now that she's a private citizen, however, she did take part in last week's RNC, delivering a speech on foreign policy.
Will Hillary Clinton try to tune in from East Timor to watch her husband's speech? Her staff isn't saying. But if her usual travel schedule applies -- every minute jam-packed with meetings, briefings and news conferences -- she may wait until she gets back home to hear from Bill Clinton directly how it went.