Presidential candidates make all sorts of promises and commitments on the campaign trail that voters use to evaluate them – but there’s an important catch: Many of the issues that consume the most ink and air time require congressional action to come into being.

The reality is that a president is limited in what they can do on their own, without Congress. But, one thing they have enormous control and influence over independent of Congress is the state of civil rights in this country.

Start with the U.S. Department of Justice, where the Civil Rights Unit has taken on widely different missions depending on the commander in chief. It can be a fierce defender of voting rights. It can be a proponent for police reform. It can be at the forefront of civil rights, a bystander or even an obstructionist, all depending on the priorities set by 1600 Pennsylvania Avenue.

The rules, policies and regulations put out by the executive branch at the direction of the president can directly advance or obstruct LGBTQ rights, reproductive rights and immigrants’ rights.

This includes, for instance, the gag rule that forbids doctors from talking to their patients about abortion services, or policies about who can serve openly in the military, or even enter our country.

The president also has the single loudest microphone in America. In a world of 24/7 media coverage, that microphone creates ripple effects throughout society.

Views on race, nationality and gender identity are heavily influenced by the one person that news outlets and channels must give airtime to on a daily basis. The president’s opinions influence not just their national party’s agenda; they shape legislative agendas at the state level as talking points are echoed across the country.

Then there is criminal justice, the state of which is guided by priorities and policies set down by the president. Such as whether to revive the federal death penalty, setting priorities for federal prosecutors across the country and the use of presidential clemency, which we’ve seen recent administrations use to advance criminal justice reform.

Let’s not forget privacy. The proliferation of invasive technologies, from facial surveillance to geo-tracking, to the amassing of data that internet users leave behind them every time they go online – these do not just raise questions about whether Google or Facebook should be able to amass, use and sell our data. They also raise questions about the government’s access to and use of that same data and technology.

The Fourth Amendment is being tested, including by the agencies that report to the president – one of the largest invasions of privacy by the government over the past two decades was at the hands of the National Security Agency NSA.

Civil rights are also a critical part of foreign policy with questions about the definition of torture, the use of drones, and indefinite detention at Guantanamo Bay all being asked repeatedly to the past few administrations with differing answers being provided.

For over two decades we have witnessed multiple presidents’ interpretations of war powers profoundly impact fundamental constitutional and human rights protections, domestically and abroad. Will the next president continue interpreting the Authorization of the Use of Military Force (AUMF) in a manner that extends the “forever war” mentality that has severely weakened individual freedoms? Or will they take steps to restore our constitutional checks and balances and reign in executive war power authority?

Candidates make many promises on the campaign trail that they cannot deliver on alone. Health care, education and infrastructure all require legislation and support from Congress. While a candidate can explain what they would like to see accomplished through collaboration with Congress, they are not in a position to promise results.

While civil rights can and are absolutely advanced or impeded through congressional action, the president is uniquely empowered to shape the civil rights landscape in America.

On this last day before the first-in-the-nation primary and during a voter’s final deliberations, it is worth taking the time to inquire where candidates stand on civil rights issues.

Unlike headline policy proposals, whomever is elected president will have the power to shape the fate of civil rights in the United States. It is worth reviewing what that fate might be before you cast a ballot.

(Jeanne Hruska is the political director of ACLU-NH.)