The former president, 56, lives in Washington but maintains a home in Chicago, which is why his name came up for jury duty there.
When he entered the jury room, he took time to shake everyone's hand and sign a few books other potential jurors had with them.
One group was called and the rest of the 220 jurors - including the 44th president - were dismissed, though Evans added that Obama said he was willing to serve had he been selected. As happens most days, would-be jurors brought books, but on Wednesday some people brought books Obama had authored in hopes he might sign them.
Obama took a private elevator with his security to the room, where he shook almost every hand.More news: Sleep Deprivation Has The Same Effect as Drinking Too Much, Says Study
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"The Former president was here at our invitation", Evans said.
While the Obamas now live in Washington, the former president and first lady Michelle Obama maintain a home in Chicago, the city where he got his political start.
Obama spent the night at his home in Kenwood before leaving for jury duty shortly after 9:30 a.m., in a motorcade of four black SUVs, a marked Chicago police SUV, and a marked Illinois State Police SUV. Like Obama, Neither landed on a jury.
Former Presidents George W. Bush and Bill Clinton were also called for jury duty post-White House. In 2004, Oprah Winfrey was on a Chicago jury that convicted a man of murder.
For his day of public service, he will presumably receive the standard payment for every Cook County juror, which is $17.20.