My Lords, I shall speak to Amendment 241A in my name. At the end of the debate at Second Reading, the noble Lord, Lord Bates, responded extensively to a wide range of questions and comments. One of them, brought up by me and a number of other noble Lords, was about the fact that we have so little information in this area. In his response, the Minister read off a whole lot of evidence and research that the Government had possession of. I was unsatisfied by that, because most of the information did not help to determine an evidence-based policy towards migration, particularly the illegal migrants who are in the country. I therefore set myself a challenge: if I was making a decision, as a Minister, on the basis of evidence, what would I want to know? If, in my business life, I was looking at market research, what would I try to determine? I then asked myself if it was possible to determine them, because that is clearly the second stage of this. I have put in the amendment the sort of information that I would want to know if I was a Minister or Secretary of State making decisions
about how I approached this subject. Illegal migrants in the country are clearly a problem: no one denies that. If they are here illegally they should not be here, and we should be able to take action. I have a list of eight or 10 things that I would want to see. I will be interested in the Minister’s response in terms of actually finding those things out. Are they, indeed, the sort of things they should know?
The second question is: is it possible to know about and explore something that is an illegal activity? There have been studies of the number of illegal migrants in the UK but I understand that the last major one—maybe by the LSE—was in 2009. It estimated that there were somewhere between 400,000 and 800,000 in the UK. There is quite a large margin of error between the minimum and maximum numbers in that estimate. Is it possible to measure illegal activities? I expect that noble Lords are aware that in May 2014 the Office for National Statistics started to include in GDP figures the amount of GDP generated by illegal drugs and prostitution. Prostitution is not strictly illegal, but in terms of how it is carried out it is broadly seen as an illegal activity and therefore had not been brought into GDP before. The total GDP for those two activities was about £12 billion; more or less 50%, or £6 billion, related to illegal drugs, and approximately the same figure related to prostitution. It is therefore possible to estimate those types of figures with a reasonable standard error, if not with certainty.
The techniques that have been used to measure illegal migration are the Delphi method, the capture-recapture method and the residual method, which has been used to make these estimates in the United States. I am not for a minute saying that this is an easy or totally accurate exercise, but for decisions around such important areas as this, which we all want to solve, we should spend a little more resource and time moving away from rhetoric and into understanding what is going on. By doing so, we might have a lot better decisions about migration management, and there might be legislation that we can all agree on, rather than taking rather normative views.