(CNN) His White House in a perpetual state of soap operatic turmoil, President Donald Trump could very well enter 2018 without a single major legislative victory to his name.

But over at the Department of Justice, it's a very different story. While Trump may be, by word of the Constitution, the most powerful person in Washington, it is his attorney general, Jeff Sessions, who has emerged as one of the most potent -- even after Trump publicly scolded him over his recusal from the Russian election meddling investigation, then expressed regret over his nomination.

But where Trump has failed to roll back former President Barack Obama's signature achievements and policies, Sessions, under the radar and without congressional tripwires at his feet, is erasing some others with startling speed.

In no particular order, the Sessions Justice Department has:

Directed federal prosecutors to pursue the stiffest possible charge in every single criminal case -- potentially triggering draconian mandatory minimum sentences the Obama administration tried to avoid on fairness grounds for non-violent offenders.

Withdrawn an Obama administration directive offering protections for transgender students who wanted to use bathrooms corresponding to their gender identity.

Reversed an Obama DOJ order that the federal Bureau of Prisons back off new deals with private facilities. "I direct the Bureau to return to its previous approach," Sessions said in a memo citing concerns that the "future needs of the federal correctional system" would be "impaired."

Launched a broad-based effort to reduce federal oversight of local police departments, like those put under increased scrutiny following investigations into alleged abuses. The deputy attorney general and associate attorney general were ordered to review lots of things, including all "contemplated consent decrees."

In a move criticized by voting rights advocates, asked state election officials in June to lay out their processes for purging voter rolls of individuals who have become ineligible due to, among other reasons, "death or change of residence." Then in August, the department changed course from the Obama years and sided with Ohio in its efforts to purge state voter rolls. (Note: these actions are not connected to the activities of Trump's controversial Presidential Advisory Commission on Election Integrity.)

Put in place a policy that could pave the way for an increase in a certain kind of civil asset forfeiture, a controversial practice -- in this case a joint federal, state and local version that some departments were accused of using to get around state law -- that allows police to seize money or property from suspects who haven't been convicted of a crime. (The DOJ says it has put new safeguards in place to prevent abuse.)

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