With Sen. Jeff Sessions of Alabama set to take over as the nation’s attorney general, it’s worth noting what exactly the job entails for the “people’s lawyer” charged with ensuring justice according to the laws of the United States.

As a member of Donald Trump’s Cabinet, Sessions is set to become the chief law enforcement officer and will retain the power to issue formal demands to state agencies, while leading the Department of Justice as the top legal council to the president.

He must be well-versed in both the U.S. Constitution and interpretations of laws all the laws that govern executive departments in Washington.

What specifically does the attorney general do?

The attorney general is responsible for an unbiased an professional lawyer presence at the head of the Department of Justice. They must also supervise other United States attorneys and marshals, ensuring protocols are followed and that constitutionality is upheld on every level of law.

In addition to overseeing the budgetary control over federal litigation attorneys, the AG will also give opinions on contentious issues before the court.

To sum it up nicely, Attorney General Edward Bates once said, “The office I hold is not properly political, but strictly legal; and It is my duty, above all other ministers of state to uphold the Law and to resist all encroachments, from whatever quarter, of mere will and power.”

What of their legal opinions?

Oftentimes, the attorney general will be asked to speak out on contentious issues that are haranguing before the court or pressing the president at a given moment.

Eric Holder, for instance, weighed in on waterboarding during his time as President Obama’s attorney general, and it was his responsibility to find a court-centered approach in the defense of charges against the Affordable Care Act.

During George W. Bush’s presidency, John Ashcroft was a key supporter of the Patriot Act — although it turned out that some of the intelligence programs set into motion by his legal understanding were, in fact, illegal. That left it up to future court decisions and the Obama administration to clean up Justice Department errors.

Outgoing Attorney General Loretta Lynch was in charge of prosecuting Dylan Roof over federal hate crimes following the shooting massacre inside a Charleston church, and has also weighed in on the re-entry to society of convicted felons.

These are just a few examples of how the nation’s top cop must lead by example, and own up to erroneous judgements.

Have we always had a U.S. Attorney General?

The office was actually established by Congress in 1789, as a part-time legal advisor to the president who was paid a low salary for upstart lawyers that were handpicked for honor and prestige that, presumably, would help them build a clientele.

The AG’s original duties were stated as “to prosecute and conduct all suits in the Supreme Court in which the United States shall be concerned, and to give his advice and opinion upon questions of law when required by the president of the United States, or when requested by the heads of any of the departments.”

In 1870 the DOJ was created, and it wasn’t until then that the Cabinet-level position held a similar significance to the offices of the secretary of state, secretary of the treasury and secretary of defense.