Before Brexit there was the immigration goal. Reducing immigration down to several tens of thousands was an objective announced by David Cameron in 2010/11. Never mind that as part
of the Single Market and thus free movement of people across the European Union this objective was all but unachievable. Politicians are obviously aware of this, so as diversion mechanism illegal migrants have been targeted through the hostile
environment policy and removal targets. However, the problem is that the UK does not have a proper registration system
and there are thousands of legal migrants (e.g., Windrush generation) that do not have proper documentation. Result: since illegal immigrants are hard to track down, bureaucrats go for low-hanging fruits – legal migrants with no or doubtful documentation.
These could be member of the Windrush generation, foreign students who supposedly have cheated on their English exams,
and even highly skilled non-EU migrants who are applying for permanent residence and get rejected on shady grounds. While one might find this approach by bureaucrats to go after legal migrants despicable, it can be easily explained by the incentives
given to bureaucrats – quantitative targets (number of people to be removed) in times of reduced resources (courtesy of the coalition’s austerity policies). It is definitely not the agents’ but the principal’s fault, in this case
the Home Secretary and the government, more generally.