Commonly known fact? If it was so commonly known you would have shoved it down my throat.  
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Sessions: DACA was an “unconstitutional exercise of authority by the executive branch.”

Fact-check: This statement seems to be Sessions’ opinion. The final arbiter of constitutionality is the U.S. Supreme Court, which has never ruled on DACA. 
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https://www.nbcnews.com/news/latino/fact-checking-attorney-general-jeff-sessions-daca-n799366
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"The U.S. Supreme Court has never ruled on DACA"
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AND THAT"S A FACT.