Funny thing, discretion.
You get pulled over for speeding and pray the cop will exercise some discretion to let you off with a warning.
Some people see a drunk driver, and get all upset when the cops exercise discretion to let him avoid a DUI arrest.
Law ‘n order types got upset with judicial discretion and voted for mandatory sentencing. But when the [expensive] prisons filled up with nonviolent victimless “crime” “offenders, suddenly judicial discretion started looking better.
The Supreme Court exercises judicial discretion all the time in deciding which which cases to grant certiorari. That gets real darned annoying in situations where every bloody circuit has been making conflicting decisions and we’d really like to see the whole country following the same rule book. But what can they do? There isn’t isn’t enough time before the heat death of the universe for SCOTUS to hear every case that someone wishes he could appeal to the Supreme cross-dressers. Discretion is required.
Presidents routinely make “signing statements,” declaring their discretion to enforce new bills/laws, when they don’t really like what Congress sent them, but don’t quite want to veto. Some people like or hate that, depending on party affiliation.
But the fact is that discretion in applying laws is nothing new, at any level.
But let one guy decide he’s going to exercise a little discretion in applying immigration laws, and suddenly it’s all illegal, unconstitutional, immoral, and fattening.