Bloke gets job, is arrested for deportation anyway

[badass]

Yes? Explain why we don't want people to come here and contribute to our economy please?

One word. Wages. You open the immigration borders and everyone in this country will be on minimum wage.

Why? Half of the planet live on less than $2 per day. Compare that to £4.85 per hour minimum wage.
If you heard that the minimum wage in some other country was £1900 per day and had open borders, if things were tight would you not be tempted to go to work there?
As a result we would be inundated woth immigrants willing to work for less then us and they would keep going down untill the wages averaged out.

[Rave]

Yes, yes, I'm aware that we can't have completely open borders and allow unlimited numbers of immigrants to come here looking for work. At a time of full employment though (which we certainly were effectively at a few months ago and are still close to now) it doesn't make sense to hold up the economy by kicking people who have jobs out of the country (or, for that matter, keeping people who have offers of work out). Protectionism is necessary only when there's a shortage of work.