Vice President Kamala Harris has a strategy in her first presidential debate to smirk whenever former President Donald Trump is talking. Whether it works is to be determined, but it’s important to understand her thinking.

If you watch her on the split screen, Harris smirks and shakes her head regardless of what Trump is saying. Her headshakes and shocked googly-eyes and muted-mic “not true” exclamations don’t correspond to her disagreements and her counterpoints. She is not actually reacting; she is simply making these faces because she knows she’s on camera.

So why does she do this?

It’s the same strategy her boss, President Joe Biden, used in his vice presidential debate in 2012.

Biden would laugh at then-Rep. Paul Ryan (R-WI) whenever he said anything and act is if everything he said was laughable and absurd. The idea here is to not look angry, but to try and act as if you think the other person is just a clown. Half the point of this is to set a tone for the crowd. The other half is to throw off the speaker.

Biden’s gambit worked. It rattled Ryan. But Ryan and Biden were more face to face than Harris is with Trump.

Also, Harris looks a little silly and schoolteacher-y when she tries to do it.

Biden didn’t care that he looked like the Joker because he was running for vice president. His only job was to make Ryan look bad.

Harris, however, is primarily trying to make herself look like a leader. I don’t think this does the trick.