The department can also show leniency to a presidents political friends. The Roger Stone case is an example. Indeed, the very possibility that it will do so can create a strong incentive to become the presidents political friend.

The presidents power over the Justice Department is potentially even more dangerous than that. The department helps to oversee the antitrust laws, and in allowing or forbidding mergers, it can play political favorites. Civil actions, and not merely criminal ones, can be polluted by the presidents electoral interest (or spite).

The Office of Legal Counsel, which sits within the department, is supposed to provide the president and the rest of the executive branch with objective legal advice. But at least some of the time, that offices judgment is anything but objective. To an uncomfortable degree, its assessment of what the president is entitled to do, as a matter of law, often fits with the presidents wishes.

In the post-Watergate era, a reasonable balance has been struck. As a matter of established norms, both Republican and Democratic presidents have usually given the attorney general a great deal of room to maneuver, especially when it comes to criminal prosecutions and ongoing litigation. In other words, norms have done the work of law.

Under President Trump, those norms have come under severe pressure. If they collapse, there would be incalculable damage to both liberty and self-government.

In light of that risk, Congress should seriously consider making the Justice Department an independent agency. Sure, a Republican-dominated Senate is unlikely to allow that to happen in the near future.

But wouldnt it be better? There are two objections.

The first involves accountability. Theres a reasonable argument that the priorities of the department, which oversees so many important questions of law and policy, should reflect the views of the American people and so the president, whom they elected.

Excerpt from:

Imagine That Donald Trump Has Almost No Control Over Justice - The New York Times