Coequal branches of government. The separation of powers between the branches of government. The president nor congress can tell the SCOTUS what to do. What congress can do is basically limited to impeachment of any of the SCOTUS justices. Which only one has been impeached, he was acquitted in the senate. Samuel Chase in 1805.

It's high past time that we start electing Americans to congress and the presidency who put America first instead of their political party. For way too long we have been electing Republicans and Democrats who happen to be Americans instead of Americans who happen to be Republicans and Democrats.