Sonnenfeld: What United Airlines got right

United names Oscar Munoz new CEO

United Airlines should be saluted for how it handled the ouster of its CEO and chairman amid a corruption probe, Yale School of Management's Jeff Sonnenfeld said Wednesday.

On Tuesday, United announced board member Oscar Munoz would replace Jeffrey Smisek as chief executive.

"The board moved quickly. They didn't put in an interim. They put the right guy in there," Sonnenfeld told CNBC's "Squawk Box." "They put somebody in there who knows what he's doing. He's been battled tested. [He's] very well thought of."

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Munoz is the former chief operating officer of rail company CSX and was a member of Continental's board before its merger with United. In a letter to employees Tuesday, he said he would focus on improving customer service, building teamwork and driving innovation.

Independent director Henry L. Meyer was named nonexecutive chairman, replacing Smisek.

Sonnenfeld said it makes sense to separate the CEO and chairman roles at a time of crisis and transition and praised United for acting nimbly to do so.

United removed Smisek following an internal probe into alleged improprieties related to negotiations with the Port Authority of New York and New Jersey. The airline allegedly revived a flight from Newark International Airport to Columbia, South Carolina, at the request of then Port Authority Chairman David Samson, who owned a home nearby.

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The Port Authority oversees Newark airport, as well as New York City's two major airports.

Shortly after the agency approved a new United hangar at Newark, as well as financial incentives for its construction, the airline moved forward with plans to resume service from Newark to Columbia, according to media reports.

United and the Port Authority have received federal subpoenas requesting information and documentation concerning their dealings with one another.

UAL CEO Smisek out amid legal probe

The company did the right thing by launching an internal investigation, said Jacob Frenkel, a former federal prosecutor and now a partner at law firm Shulman Rogers.

"When quality corporations have senior executives who are caught up in some set of allegations, now corporate discipline requires that they remove themselves or be removed from those positions of leadership," he told "Squawk Box."

Frenkel said traditional bribery in which money changes hand is no longer common. The guts of the federal investigation will boil down to whether there was a bribe, quid pro quo, or kickback.

"The fundamental issue that has to be proven ... is that there was criminal intent here, that there was something of value that was given in exchange for an official act or expectation of an official act."

The defense would have to prove that any arrangements under investigation were bona fide corporate needs and there was no quid pro quo. That would require proving there was a business logic to restarting the Newark-to-Columbia route, which was reportedly shut down in the first place because it lost money.