RNA - In a damning 90-page report released on Friday, the rights group accused the alliance's investigative body, the Joint Incidents Assessment Team (JIAT), of "absolving coalition members of legal responsibility in the vast majority of attacks", Middle East News reported.
"Many of the apparent laws-of-war violations committed by coalition forces show evidence of war crimes," HRW said in the report.
"JIAT investigations show no apparent effort to investigate personal criminal responsibility for unlawful air attacks. This apparent attempt to shield parties to the conflict and individual military personnel from criminal liability is itself a violation of the laws of war," it added.
Previous investigations by the Saudi-led alliance also absolved itself of any real responsibility and instead put the blame on the Ansarullah, according to the report.
The HRW said that JIAT often appeared to find that an air attack was lawful "solely because the coalition had identified a legitimate military target, but did not appear to consider whether the attack was lawfully proportionate or if precautions taken were adequate".
"For more than two years, the coalition has claimed that JIAT was credibly investigating allegedly unlawful air attacks, but the investigators were doing little more than covering up war crimes," Sarah Leah Whitson, HRW Middle East director, stated, adding that "governments selling arms to Saudi Arabia should recognize that the coalition’s sham investigations do not protect them from being complicit in serious violations in Yemen".
The US, UK, Canada, France and Spain have all sold weapons to Saudi Arabia in recent years despite repeated petitions from human-rights groups. Some of those weapons have been used in the conflict. Washington has been the biggest supplier of military equipment to Riyadh, with more than $90bn of sales recorded between 2010 and 2015.
Following a recent air attack on a school bus that killed 40 children, individual members of congress called on the US military to clarify its role in the war and investigate whether support for the air raids could render American military personnel "liable under the war crimes act".
Saudi Arabia has been striking Yemen since March 2015 to restore power to fugitive president Mansour Hadi, a close ally of Riyadh. The Saudi-led aggression has so far killed at least 17,500 Yemenis, including hundreds of women and children.
Despite Riyadh's claims that it is bombing the positions of the Ansarullah fighters, Saudi bombers are flattening residential areas and civilian infrastructures.
Reports by independent world bodies have warned that the Saudi-led air campaign against Yemen has driven the impoverished country towards humanitarian disaster, as Saudi Arabia's deadly campaign prevented the patients from travelling abroad for treatment and blocked the entry of medicine into the war-torn country.
Yemen is the world’s largest humanitarian crisis with more than 22 million people in need and is seeing a spike in needs, fuelled by ongoing conflict, a collapsing economy and diminished social services and livelihoods.
A UN panel has compiled a detailed report of civilian casualties caused by the Saudi military and its allies during their war against Yemen, saying the Riyadh-led coalition has used precision-guided munitions in its raids on civilian targets.