1. Very pleased that my article with @MBEGriffiths about the hostile environment policy has been published in the journal Critical Social Policy, after over four years of work on it. Thread on some of what we say.

2. We look at the origins, extent, operationalisation and impacts of the hostile environment in the labour and housing markets, public services, pricing, healthcare and education.

3. It is a policy over which, by design, the government lost control because it relies on third parties to implement it on the ground.

4. The modern policy has long antecedents but from around 2012 the approach was dramatically and recklessly expanded and any pretence at 'balance' by making immigration compliance easier was abandoned.

5. We argue the hostile environment was never an evidence-driven policy expected to achieve measurable immigration outcomes but rather an ideological policy propelled by a set of moral values.