Image copyright Getty Images Image caption Ms Clinton served as Secretary of State under President Barack Obama

Democratic presidential candidate Hillary Clinton has said appointing President Barack Obama as a Supreme Court justice is a "great idea".

At a campaign event in Iowa, a voter asked Ms Clinton if she would consider appointing Mr Obama to the Supreme Court if she is president.

She noted that the next president could appoint up to three Supreme Court justices, ABC News reports.

"Wow, what a great idea. No one has ever suggested that to me," she said.

"I love that, wow. He may have a few other things to do but I tell you that's a great idea."

Ms Clinton made the remarks to a crowd of 450 people in a ballroom.

"He's brilliant, and he can set forth an argument, and he was a law professor, so he's got all the credentials," she said.

"Now we do have to get a Democratic Senate to get him confirmed so you're going to have to help me on that, OK?" she said.

Ms Clinton, the Democratic frontrunner, served as Secretary of State under Mr Obama.

Mr Obama told the New Yorker in 2014 he "loves the law" but he was not sure it would be the right job for him.

"I love the law, intellectually," Mr Obama said when asked if he would consider being a Supreme Court justice.

"I love nutting out these problems, wrestling with these arguments. I love teaching. I miss the classroom and engaging with students.

"But I think being a justice is a little bit too monastic for me."

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