Commerce Secretary Wilbur Ross praised President Trump for a trip to Saudi Arabia that was so successful it didn't draw a single protester.

One problem: Protests are illegal in Saudi Arabia.

In an interview Monday with CNBC, Ross said he found it "fascinating" that there was not a "single hint" of protests during Trump's visit to the kingdom.

"Not one guy with a bad placard," Ross observed.

Interviewer Becky Quick pointed out that the reason might not be as simple as Ross seemed to suggest.

"That may not be necessarily because they don't have those feelings there, but because they control people and don't allow them to come and express their feelings quite the same as we do here," she said.

Wilbur Ross touts the lack of protests in Saudi Arabia during Trump's visit (maybe it's because protesters are jailed & sometimes beheaded?) pic.twitter.com/DQIENgtopz — Brian Klaas (@brianklaas) May 22, 2017

Ross told Quick that her point could be true "in theory."

"But boy, there was certainly no sign of it, there wasn't a single effort of any incursion," he said. "There wasn't anything. The mood was a genuinely good mood."

Related: Tillerson holds briefing in Saudi Arabia without US press

The kingdom banned protests and marches in March 2011, during the Arab Spring, the series of pro-democracy demonstrations in North Africa and the Middle East. That ruling formalized what was already a criminal offense in Saudi Arabia, according to Human Rights Watch.

"Secretary Ross's remarks demonstrate a complete lack of understanding of the situation on the ground in Saudi Arabia," said Adam Coogle, a Middle East researcher for the organization. Coogle said anyone who engages in public protest can be jailed for up to 15 years.

"There is no tolerance for public dissent in Saudi Arabia," he added.

Ross' office declined further comment.

The Saudi government has continued to crack down on dissidents in the years since the Arab Spring.

In early 2013, about 160 people were arrested by Saudi security forces after they protested other jailings in the country.

Later that year, the Saudi interior minister warned against women who were caught flouting its ban on women drivers.