[lock-the-spock]

It's a member of the European parliament asking a question to the European Commission (the EU executive). The reply is linked at the top of the page, but note that both question and answer are by now quite dated.

> Overall, at the end of 2016, 630 North-Korean citizens were holding a valid residence permit in the EU for work purposes, predominantly in Poland (534).[1]

> When processing the applications for residence permits for work purposes, it is the responsibility of the national authorities to check that the conditions are fulfilled, in line with the EU acquis on legal migration, working conditions and on health and safety at work.

> The EU acquis on legal migration ensures that third-country nationals working in the EU benefit from equal treatment with nationals in terms of remuneration, access to social security systems and other conditions of employment. It is the responsibility of the national authorities, including the labour inspectorates, police and judicial authorities to ensure that the prohibition of forced labour is enforced.

> The Commission will keep monitoring the transposition and application of the different instruments by Poland.

[gambiting]

Remember that Poland has been caught red handed recently handing out schoengen visas(to the tune of 200k visas issues without proper checks) for cash, so I'd expect the enforcement of law around this to be very lax.