Updated

Justin Timberlake is under investigation.

The "Can't Stop the Feeling!" singer may have broken a Tennessee state law while snapping a photo of himself while voting on Monday.

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"Hey! You! Yeah, YOU! I just flew from LA to Memphis to #rockthevote!!! No excuses, my good people! There could be early voting in your town too," Timberlake wrote on Instagram, along with a photo of himself and his ballot.��

Timberlake, who's an outspoken supporter of Hillary Clinton, is now under investigation by the Shelby County District Attorney's office for taking that selfie.

"The Shelby County DA's office was made aware of a possible violation of state election law, the matter is under review by our office," an official at the Shelby County DA's office told ET on Tuesday.

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Last year, Tennessee Governor Bill Haslam signed a bill that prohibits people from using cell phones to engage in telephone conversations, recording, or taking photographs or videos while inside a polling place. The bill, which does allow for the use of phones for "informational purposes to assist the voter in making election decisions," was passed in an effort to prevent voter fraud.

Under this new law, Timberlake's selfie could be considered a misdemeanor and if found guilty, the 35-year-old singer could face up to 30 days in jail and a potential fine of $50.

ET has reached out to Timberlake for comment.

Additional reporting by Steven Wilks.