On August 9, one day after the Pentagon notified Congress of its intention to sell $1.2 billion in weapons systems to Saudi Arabia, the Saudi-led coalition resumed airstrikes on Yemen’s capital, Sanaa, after peace talks that began in April shut down. One strike hit a potato chip factory, reportedly killing 14 civilians. It was the third time the factory compound had been bombed – one of many instances in which the coalition of nine Arab states has unlawfully attacked civilian structures in an air campaign that began in late March 2015. Over the next few days, the coalition also hit a school and a Médecins Sans Frontières-supported hospital, marking the fourth attack against an MSF facility since the beginning of the war.

Since then I have interviewed hundreds of Yemeni men, women and children whose homes, markets or workplaces were damaged or destroyed in airstrikes that had no evident military target.

For 16 months the Saudis and their coalition have carried out air and ground operations against the Houthis, a Zaidi Shia group from northern Yemen that overran most of the country in late 2014. Fighting has resulted in the deaths of at least 3,700 civilians, most from coalition bombings, according to the United Nations.

Direct US support for coalition airstrikes, such as providing targeting intelligence and in-air refuelling, has made the United States a party to the conflict under international law. More recently the US has deployed some troops in Yemen to aid coalition members and its own campaign against the Yemeni-based Al-Qaeda in the Arabian Peninsula. And while the US has long sold fighter planes and other advanced weaponry to Saudi Arabia as part of its broader Middle East policy, those sales have continued despite increasing evidence that the Saudis and their partners are using them in unlawful attacks killing civilians in Yemen.

Human Rights Watch and others have been urging Congress to press the Defense Department to use its leverage with the Saudis from its direct military support and weapons sales to curtail unlawful attacks and more seriously investigate past ones. The latest congressional notification offers members of Congress a new opportunity to make that case again. By introducing a resolution of disapproval in the next few weeks, any member can put the brakes on the sale and use their opposition to demand action from the Pentagon and the Saudis.

The Saudis need more than gentle prodding. The laws of war require states to investigate allegations of war crimes and hold those responsible to account. After nearly a year-and-a-half of international pressure and mounting abuses, the Saudi government announced findings of preliminary investigations into eight widely publicized coalition airstrikes causing civilian casualties. The coalition-appointed panel of investigators recommended compensation for victims of only one—the July 24, 2015 bombing of two residential compounds for workers at the Mokha Steam Power Plant and their families that killed at least 65 civilians. 

The panel blamed the faulty targeting on “inaccurate intelligence information” rather than deliberate or reckless acts by the personnel involved. But this admission that the attack was wrongful represents a real change in tone.

After Human Rights Watch released a report from the bombed-out site, the coalition’s military spokesman, Saudi Gen. Ahmad al-Assiri, denied that coalition aircraft were responsible for the attack and said our report wasn’t credible. He later claimed that my colleagues and I had not been on the ground during the war, despite the hefty written, video, and photographic material we have issued documenting our trips there.

The panel also said the coalition should have warned medical staff at the Doctors Without Borders-supported Haydan hospital in Saada governorate before bombing it six times. But the panel dismissed the seriousness of attacking a hospital by concluding there had been no “human damage.” Besides the two patients who the aid group’s country director told me were injured, the attack destroyed the emergency room of the hospital, which had received about 150 cases a week. It was the only medical facility within an 80-kilometer radius, making the “human damage” of the attack incalculable.

The panel also concluded that a February 27, 2016 attack on a village marketplace didn’t kill any civilians, while we documented 10 civilian deaths, including a woman and four children. In an attack on another marketplace on March 15 that United Nations research and ours found that 97 people died, the panel incredibly said it saw no proof of civilian casualties. One man told us he lost 17 relatives and another lost 16.

The coalition’s examination of attacks is a reversal of past practice, but there’s a long way to go before its investigations can be considered credible, transparent, and impartial. Since the Saudis haven’t released details about the panel members or the actual reports on each incident, it’s hard to know why their findings are so different from what we and the UN found on the ground.

There are also many more airstrikes that need to be investigated. It is unclear how the panel chose these 8 strikes over the more than 70 apparently unlawful airstrikes that we and Amnesty International have documented, and the more than 100 that the United Nations has. These documented coalition strikes have killed nearly 1,000 civilians.

For instance, a March 30, 2015 strike on a camp for internally displaced people killed at least 29 civilians and another strike a day later on a dairy factory near the Hodaida port killed at least 31. On May 12, the coalition struck a civilian prison in the western town of Abs, killing 25 people.

That same day, aircraft dropped at least five bombs on a marketplace in the town of Zabid, killing at least 60. A July 4 attack on another marketplace in the village of Muthalith Ahim killed at least 65. On October 7, the coalition bombed a triple wedding in the village of Sanaban, killing 43 civilians, including 13 women and 16 children.

Also striking is the panel’s failure to address the use of internationally banned cluster munitions. Human Rights Watch and Amnesty International have documented 19 cluster attacks that killed over 20 civilians, some of which used US-supplied munitions. A total of 118 countries have banned cluster munitions under the 2008 Convention on Cluster Munitions due to the threat they pose to nearby civilians at the time of attack and afterward. Yemen, the US, and Saudi Arabia and its coalition members should join the convention.

The families who lost their loved ones in the Mokha power plant bombing should receive swift and adequate compensation, In fact, the victims of all the unlawful attacks should receive compensation, which the coalition is required to provide.

Unless the panel investigates all alleged unlawful coalition attacks during this devastating war and does so in accordance with international standards, Saudi Arabia and other coalition members should agree to an independent international investigation into serious violations by all parties to the conflict so that accountability is ensured. The victims of these attacks have the right to know on whose watch their family members were killed.

For its part, Congress should not approve weapons sales to a government that cannot seem to stop its military from committing war crimes nor bring itself to seriously investigate the crimes that have already occurred. Cutting sales is the most powerful form of leverage that the US has in this war, and continued sales will instead send the clear message to the coalition that there is no cost to killing hundreds of civilians with impunity.