THR the rise of the Abstention Doctrine in Federal Courts.
The abstention doctrine is invoked when lawsuits involving the same issues are brought in two different court systems at the same time, such as federal and state courts. The doctrine allows the federal court to decline jurisdiction over the case to avoid conflict with the state courts. Recently, it's been criticized for being invoked for political reasons. Donald J. Trump for President, Inc. v. Boockvar (2020), had federal courts abstain from intervening in Pennsylvania’s mail-in voting rules, deferring to state courts.