An unpublished letter to the Guardian editor

Dear Editor,

Your recent article on European public perceptions of legal vs illegal migration rightly draws attention to widespread overestimation and misunderstanding. However, differences between headline findings in surveys merit careful interpretation.

In a UK study we released in November 2025 (Lessard-Phillips and Sigona 2025) based on a survey conducted earlier in the year with YouGov (as for the survey you are reporting on) respondents were asked to estimate the share of migrants with irregular status within the foreign-born population. As in your reporting, we found the majority of the public overestimate migrant irregularity in the country, but it was more contained and patterned, varying significantly by age and political affiliation. Younger respondents and Labour or Liberal Democrat voters were often more likely to underestimate rather than overestimate the scale.

One reason for the apparent discrepancy lies in how questions are asked. Asking whether “most migrants are illegal” invites a binary judgement shaped by media salience and political rhetoric, rather than a numerical assessment of population shares. When respondents are prompted to think quantitatively and given a clear denominator, their answers tend to be more differentiated.

Our findings also suggest that misunderstanding is driven less by ignorance of numbers than by distorted beliefs about how irregularity arises. Respondents overwhelmingly associate irregular status with border crossings and asylum claims, while routine bureaucratic routes — such as visa expiry or loss of status through work — are far less recognised.

These nuances matter. Addressing public concern requires not only correcting misperceptions of scale, but also broadening the narratives through which irregular migration is understood.

Yours sincerely, Nando Sigona and Laurence Lessard-Phillips