Actually you don't need to be an ethnic minority to be made an extenuating circumstance and made an example of. We could do the same with white rapists or child molesters in Asia. Perhaps we already have?
They would certainly pose a danger to our society if they returned home, maybe it should be routine course of action, no need for extenuating circumstances.
As it has been mentioned, most whites in the UK are not dual national, so they are not entitled to citizenship elsewhere so by default they can return to the UK and face trial etc or be extradited to the UK regardless of the 'crime' commited or the colour of their skin.
There are many cases where UK nationals have served time abroad, then sent back to the UK. But SB has not served anytime let alone charged with a crime.
Arresting UK nationals of all colours and creed of suspected criminals etc upon arrival is routine course. You and I just don't get to read about them in mainstream media.
SB is an immigration case first, she hasn't been charged with a crime in the UK or elsewhere, but her intent was clear, plus her case is made more complex by the fact she now has a child, which does not grant her automatic UK citizenship hence an extenuating circumstance. It's the child that is stateless; and the child was not born in the UK. This is the crux of the matter. This is the reason SB wants to return; using her child as a free pass and expecting sympathy from the nation.
Now assuming SB is allowed back in the UK; her child is now a welfare burden while she is facing what not in the UK. Rule number 1 of UK immigration - you must prove you will not be a burden to the state.
Yes, just because we have rapists, child molesters, terrorists etc in the UK doesn't mean we let more into the UK, but thanks to the like of interpol etc its easy to track suspected criminals.
When you have time, read up on the ECO guidelines for UK immigration. ECO - Exit Control Officer.
It highlights all the rules and requirements and the violations for UK immigration.
Irony is, if SB didn't have a child, the UK would more than likely allow her in. But coupled with her lack of remorse, lack of regret, and clear intent, the ECO guidelines are very clear - she must be denied entry to the UK.