Earlier this month, a dramatic event occurred in the war in Yemen that could even shock those numbed by the continued pace of civilian casualties.

A military craft and helicopter reportedly engaged in an attack on a boat carrying over 140 Somali refugees killing upward of 42 people on board.

Despite initially conflicting accounts, the evidence points to the Saudi-led coalition.

On March 24, the U.N. reported that according to survivors’ accounts, the vessel “was hit by shelling from a Coalition warship, without any warning, followed by shooting from an Apache helicopter overhead.”

What has not received adequate attention is the potential role of the United States.

It will take time to sort out the details of what exactly occurred, but this potentially brazen attack comes just as the White House is considering increasing its involvement in the Saudi-led operations against the Iranian-back Houthi militia in this Middle East nation.

So, how might the United States be implicated given that it didn’t come anywhere close to pulling the trigger?

The United States provides not only attack helicopters for the leading members of the coalition, the Saudis and the United Arab Emirates. Official records reveal that the United States also provides parts and technical support that presumably attaches to the life of the helicopters.

The Defense Department’s public notification of a $1.9 billion sale of multi-purpose helicopters used in maritime operations to Saudi Arabia in 2015, for example, includes a guarantee of “U.S. Government and contractor engineering, technical and logistics support services.”

This is a boilerplate part of the agreements for U.S.-manufactured Apache and Blackhawk helicopters sold to the Saudis. (The same holds true for US-manufactured helicopters sent to the UAE.) The Department of Defense has also had a substantial military presence in Saudi Arabia to help them use the equipment.

Back in 1994, the Justice Department’s Office of Legal Counsel warned U.S. officials that they could be found guilty of aiding and abetting an offense by providing intelligence information to foreign governments who used that information to shoot down civil aircraft.

To illustrate the point, the Justice Department used the example of “the seller of gasoline who knew the buyer was using his product to make Molotov cocktails for terroristic use.”

The U.S. provision of attack helicopters is even more directly tied to the acts of the Saudis than the hypothetical seller of gasoline or a gun dealer.

The United States is responsible for continued maintenance and support of the sold equipment, the Saudi coalition has repeatedly engaged in bad acts, and the United States retains the ability to suspend its logistical support.

In the case of these highly sophisticated helicopters, the U.S. support is an irreplaceable part of the equation.

“The Saudis have used weapons we have sold them in Yemen in ways that undermine our foreign policy objective of ending the war and easing humanitarian suffering there,” Tom Malinowski, who served as the top human rights official at the State Department until January 2017 told Just Security.

“There is a strong policy argument for suspending some sales, as President Obama did, until concerns about these kinds of incidents are resolved, and a possibility of legal jeopardy for U.S. officials if sales continue despite continuing evidence of violations of the laws of war.”

Even if we were not operating in the realm of criminal activity, under international law one State can be held legally responsible for assisting another in internationally wrongful acts. Those legal risks increase if the recipient is engaged in continuing and widespread violations.

As a policy matter, this is the reality facing the U.S. decision of how close to get to the Saudi-led operations in Yemen.
But how do we know the attack on the refugees was carried out by the Saudis or Saudi-led coalition? We don’t for sure. But the real question is how much the U.S. government knows.

Several eyewitness accounts describe the helicopter attack on the boat, including video of survivor statements after they came ashore. “The survivors said they came under attack from another boat at 9 p.m., the crew used lights and shouted to signal this is a civilian boat,” ICRC spokeswoman Iolanda Jaquemet told Reuters. “Nevertheless, it did not have any effect and a helicopter joined in the attack,” she said.

Only the coalition has military helicopters. Their opposition, the Houthis, don’t. Somalia has also fingered the coalition. The Somali foreign minister Abdisalam Omer said on state-run radio, “What happened there was a horrific and terrible problem inflicted on innocent Somali people. The Saudi-led coalition fighting in Yemen is responsible for it.”

Somalia is itself a member of the coalition, and thus likely has more information than other governments on coalition activity.

The UAE, a more prominent member of the coalition who has been active in the area, in an unprecedented step called for international investigation into the incident. This may serve the UAE’s effort to cast themselves as the more responsible partner compared to the Saudis.

“An official source in the UAE Armed Forces,” according to Emirates state-run news, also “declared that the UAE Armed Forces have clearly recognized the non-military nature of the boat which was carrying a large number of civilians. The source said that in the light of this information, the UAE Armed Forces adhered to the strict engagement rules preventing them from targeting any non-military targets.”

The source added that there was a possibility the boat was targeted by Houthi forces.

The UAE statement implicitly contradicts the spokesperson for the coalition who denied that the coalition was even operating in the area. That denial is, in any case, hard to square with the coalition’s continuing and increased naval operations around the Hodeida port.

It would also not be the first time that categorical denials of wrongdoing by the Saudi-led coalition’s spokesperson have proven false.
The Saudis have not supported an international inquiry into the matter. In the past, Riyadh has worked—with the acquiescence of the U.S.—to block efforts at the U.N. to form an international body tasked with investigating the entire conflict.

“As Yemen’s war enters its third year, the coalition has carried out what looks likely to be another war crime, this time with a helicopter attacking a boat filled with refugees and migrants fleeing conflict,” Kristine Beckerle, Yemen researcher at Human Rights Watch, told Just Security.

“Instead of suspending weapons sales to Saudi Arabia, given that U.S. arms have been repeatedly used in unlawful coalition attacks throughout this war, the US appears poised to authorize even more sales, once again risking complicity in future coalition attacks, and potentially exposing U.S. individuals to criminal liability for aiding and abetting coalition crimes.”

In December, the Obama administration suspended the sale of precision guided munitions to Saudi Arabia after the Saudis used such U.S. manufactured weapons in the strike on a funeral home. A senior US official told reporters at the time that there was “absolutely no justification for the strike.”

The question that the U.S. administration will face is whether the Saudis are responsible for this most recent incident and whether they can be trusted not to repeat this kind of attac if so.