CNN’s Brianna Keilar questioned the maturity of Democratic California Rep. Ted Lieu on Monday after he wore a “Trump Putin ’16” shirt during a Facebook Live broadcast.

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Lieu called Trump’s tweets “highly disturbing” and “inappropriate” during a CNN interview Monday, but Keilar pointed out the apparent hypocrisy given Lieu’s own childish behavior on social media.

“I checked out your Facebook Live from last week where you talked about the health care bill, and the thing that struck me was really what you were wearing,” Keilar said. “You’re wearing a ‘Trump Putin 2016’ shirt. And you’ve tweeted about the president, you’ve called him ‘dumb as a rock.'”

“As you lob these criticisms at Donald Trump, is this the type of behavior that helps add to the maturity of discourse?” she asked.

Lieu argued that he uses the phrase “dumb as a rock” because Trump uses it, but Keilar wasn’t buying that line of reasoning.

“But that’s what [Trump] does,” she pushed back. “He says he’s quoting other people…he says, ‘I’m using someone else’s words.’ And you wore this t-shirt — can you speak to that for me?”

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Lieu said he feels the t-shirt is “accurate” because Trump does not bring up Russian meddling in elections.

“He has this very strange and bizarre relationship with Russia,” Lieu argued.

Keilar still contended that Lieu wasn’t conducting himself in a mature manner.

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