John McCain is no stranger to civil service. As his Twitter followers learned Monday, however, being a war hero and longtime member of Congress doesn't exempt McCain from jury duty.

Reporting for #juryduty this morning at the Maricopa County Superior Court in #Phoenix - let's see if I'm picked! — John McCain (@SenJohnMcCain) August 12, 2013

"Doing my civic duty for a change," McCain told AZCentral.com as he made his way into the courthouse. "We're off to get those criminals."

About four hours after that tweet, McCain updated his status:

Just got selected for a panel - let's see what happens next #juryduty — John McCain (@SenJohnMcCain) August 12, 2013

McCain, who has served as a member of Congress — first the House, then Senate — for more than three decades, said he was called "several times" in the past, but had never been picked to serve on a jury. "But you never know," he told AZCentral.

It wasn't long, however, before we found out that Monday probably wouldn't be McCain's lucky day:

Not selected for this jury trial, but may need to report back this afternoon #juryduty — John McCain (@SenJohnMcCain) August 12, 2013

Got word I'm done with #juryduty today - I appreciate the Court staff's dedicated work & all #Arizonans who serve on our juries — John McCain (@SenJohnMcCain) August 12, 2013

Could McCain have actually been selected to serve? Judy Stinson, associate dean at the Sandra Day O’Connor College of Law at Arizona State University, said, in theory, yes.

"It's possible," Stinson told Mashable. "It would be surprising."

Stinson said even though McCain could be deciding the fate of one of his constituents, it wouldn't necessarily be considered a conflict of interest. She added that it would be "very difficult" for the other jurors not to give him "undue weight" when coming to a decision.

For McCain to be selected, the judge would have to be convinced that his presence would not bias the other jurors' opinions.

Composite image: Flickr, Medill DC, Twitter