Former Vice President Joe Biden told Sen. Kamala Harris (D-Calif.) that it would be unconstitutional to ban semi-automatic weapons by executive order without congressional approval, as she has proposed.

“Instead of saying ‘no we can’t’ lets say ‘yes we can,'” Harris said to Biden, referring to former President Obama’s 2008 campaign slogan.

“Lets be constitutional. We’ve got a constitution,” Biden said to Harris.

The exchange between Biden and Harris took place during the Democratic presidential debate on Thursday evening.

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