The Home Office’s advisers on immigration policy have once again warned that its ability to scrutinise policy proposals is being hampered by poor access to data.
In a letter to digital secretary Oliver Dowden, Migration Advisory Committee chair Brian Bell said the MAC continues to face “challenges in accessing data and it is a lengthy process”, despite the government’s apparent drive to improve its use of data in evidence-based policy.
In the letter, Bell welcomed efforts set out in the National Data Strategy, which is currently under consultation, to take “a proactive approach on data”. Especially welcome is the drive to modernise data sharing across government and transform how data is used to make public services more efficient.
As an independent and evidence-based advisory body, data is critical to the MAC’s goal to “maximise the welfare of the resident population”, he added.
But he said that while the MAC had made “good progress” working with departments to access specific data sets, it was still having difficulty accessing data that would enable members to better understand the impact of the Home Office’s new immigration policy in a timely way.
Prompt access to such data is “essential” to ensuring the MAC can provide recommendations on the new system – which will come into effect after the end of the Brexit transition period on 31 December – and other policies based on the “best possible evidence”.
He said the data strategy should enable the MAC and other advisory bodies to carry out the research it needs to do – and that a standardised process should be put in place for advisers to access relevant data, supported by principles governing where and how access is granted.
“There is huge untapped potential in linking datasets across government, which would enable us to robustly measure the impact of the new immigration system during a period of huge change,” Bell said.
Bell's letter also chastised the Home Office for failing to provide some important data in a format the MAC could use.
"As part of our recent report on the points-based system for immigration, we also made recommendations on ensuring the retention of historical visa data in a usable format for research purposes," he said.
"This is essential for enabling us to learn lessons from previous policies and to draw insights which could improve the design of future immigration policies."
The MAC chair also noted the committee's reliance on external research and evidence, incuding analysis by non-government researchers and academics. He called for the Department for Digital, Culture, Media and Sport, which is leading work on the strategy, to come up with “consistent and transparent processes across government for external experts to access appropriate data for research purposes”.
“Given the growing importance of administrative data, there would be significant benefit in having a consistent and transparent processes across government for external experts to access appropriate data for research purposes,” he said.
Bell’s letter noted that the MAC had made “many recommendations over the years on improving our access to data: this increases the range and quality of advice we can provide the government”.
In January his predecessor, Alan Manning, wrote to home secretary Priti Patel complaining of the same "perennial problem".
“The paucity of data and difficulty of access makes assessing how well migration policies are working problematic and this risks sub-optimal decisions being made,” he told the home secretary.
Manning wrote: “In our past three reports, including the one published today, we have emphasised the ongoing challenges we have faced accessing data and the significant untapped potential offered by linking datasets held across government to enable improved analysis on migration."
Manning also called for the new immigration system to include “more active monitoring and evaluation than now of how it is working as there is inevitably uncertainty about impacts”.