There have been mixed reports into the effectiveness of the programme’s vetting.
A 2022 audit carried out by the Office of Inspector General (OIG), external – a US government oversight body – found that “some information used to vet evacuees through US Government databases (such as name, date of birth, identification number, and travel document data) was inaccurate, incomplete, or missing”.
The OIG said this problem was partly as a result of the DHS not having a list of Afghan evacuees “who lacked sufficient identification documents”.
It also reported that US Customs and Border Protection (CBP) “admitted or paroled evacuees who were not fully vetted into the United States”.
Two years later another OIG audit of the scheme, external found weaknesses in the government’s ability to identify potentially negative information (such as national security concerns) about some Afghans parolees.
However, earlier this year the OIG commended the FBI, external for its role in screening Afghans on the scheme.
“Overall we found that each of the responsible elements of the FBI effectively communicated and addressed any potential national security risks identified,” it said.
As well as reviewing audits of OAW, BBC Verify contacted several experts for their views on the vetting process.
Alex Nowrasteh, an immigration analyst at the Cato Institute think tank, said the programme “was more inconsistent than usual by OIG accounts and compared to the more intensive refugee review process”.
“Because of the chaotic nature of the evacuation, information was lost and some checks weren’t run until the migrants were already out of Afghanistan.”
Jennie Murray, President and CEO of the immigration advocacy group the National Immigration Forum, told BBC Verify she was present at the US military bases where evacuees were initially processed.
“Evacuees were processed on military bases and held for several weeks, and even months, until they were ready for entrance into the United States. This is when the security vetting and medical screening was processed, extensively”, she said.
“Even the best vetting can’t predict the future. He [Lakanwal] could have had a clean record, been an appropriate candidate for humanitarian protection, and then something changed.”
In the four years since the evacuation, thousands of Afghans have safely resettled in the US and this is the first major incident, Ms Murray said.
“The fact that one person committed a horrific act doesn’t mean other Afghans now pose a threat,” she added.