The possibility that Donald Trump's son-in-law, Jared Kushner, could fill a senior position in the White House raises thorny legal questions – one of which is whether it would run afoul of a federal anti-nepotism statute. Kushner was a close adviser to Trump throughout his campaign, but to officially employ Kushner in the White House would mean navigating the ambiguities surrounding the five-decades-old law.

Congress passed the anti-nepotism law in 1967. It's widely perceived that the lawmakers who wrote the statute were motivated in part by President Kennedy's nomination of his brother Robert as attorney general. But the legislation was also directed at much lower-profile nepotism at the time. For example, it was fairly common for congressmen to hire their wives to work in their offices, and many lawmakers wanted to stop that practice.

What the anti-nepotism law says

The federal anti-nepotism statute provides:

"A public official may not appoint, employ, promote, advance, or advocate for appointment, employment, promotion, or advancement, in or to a civilian position in the agency in which he is serving or over which he exercises jurisdiction or control any individual who is a relative of the public official."

"Public official" is defined in the law to include the president, and the statutory definition for "relative" includes son-in-law. Based on that alone, you might think it's a slam-dunk case to bar Kushner from working for his father-in-law at the White House.

Not so fast.

What's not settled law is the definition of "agency." The heart of the debate: Does the White House – or the Executive Office of the President – count as "agencies" under this statute?

How Hillary Clinton's case could help Kushner

Perhaps the legal precedent cited most often to make a case in Kushner's favor is from a 1990s lawsuit involving, of all people, Hillary Clinton.

When President Bill Clinton appointed his wife to chair the Task Force on National Health Care Reform, a lobbying group filed a lawsuit in the D.C. courts. The central legal question in that case wasn't actually about the anti-nepotism statute – it was about whether Hillary Clinton's task force had to publicly disclose records.

But almost as a passing mention in the D.C. Circuit's 1993 opinion, the court said that the federal anti-nepotism statute does not appear to cover staff in the White House or in the Executive Office of the President. Judge Laurence Silberman wrote, "So, for example, a president would be barred from appointing his brother as attorney general, but perhaps not as a White House special assistant."

There's plenty of disagreement in the legal community about whether that bit from Judge Silberman's opinion is legally binding because it wasn't part of the reasoning for the central holding in the case.

Courts have also held in the past that parts of the Executive Office of the President are not agencies when it comes to the Freedom of Information Act, but it's unclear whether those legal precedents would be controlling when applied to the anti-nepotism statute.

The intent of the statute

For many ethics and legal experts, excluding White House jobs from the reach of the anti-nepotism statute just doesn't make sense.

"Nepotism practices undermine the credibility of public officials, public confidence in government," said Kathleen Clark, a law professor at Washington University in St. Louis. "It can undermine morale of public employees. I just don't see any justification for carving out an exception to the White House."

Kushner could likely escape the reaches of the anti-nepotism statute if Trump retains him as a government contractor or as an informal, unofficial adviser.

But even if the Trump White House could find a way to circumvent the law, there's a perception cost.

"I think the American public just feels there's something wrong about setting up a dynasty around you, having your family around you officially advising you," said Larry Noble, general counsel of the Campaign Legal Center. "You don't want the White House to look like a family business."

The statute provides that violators must give up compensation. That strikes Ken Gross, a government ethics lawyer, as an ineffective way to enforce the law.

"So it sounds like you could have someone in an unpaid position, and then they've already suffered the penalty for violating the provision, and presumably, they would go on their merry way as an unpaid member," said Gross.

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