(CN) - Like most member states of the European Union, the Netherlands requires immigrants to make an effort to become part of Dutch society.
While EU law requires member states to give permanent-residency status to immigrants who have resided continuously within their borders for five years, the nations are allowed to require integration - typically language proficiency and a working knowledge of their society and culture - before granting permanent residency.
But whether the integration requirements also extend to foreign nationals who already have permanent-residency status lies at the heart of a pair of cases being debated at the Netherlands' Higher Social Security Court.
In one case, a U.S. citizen identified in court filings only as "P" has been living in the Netherlands since 2002 and became a permanent resident in 2008. That same year, officials in Breda informed her that Dutch law required her to pass an integration examination or face a fine - a process she began but never finished due to health concerns.
Meanwhile, New Zealand national "S" caught heat from authorities in Amstelveen in 2010 - three years after she achieved long-term residency status - for not taking her integration test. The two women challenged the respective decisions in the Dutch court, arguing that since they already held permanent legal resident status the integration requirement did not apply to them.
The Dutch court asked the European Court of Justice to weigh in on whether member states could still demand integration, even of long-term legal residents.
In an advisory opinion for the European high court issued on Wednesday, Advocate General Maciej Szpunar acknowledged that EU law requires member states to make immigrants permanent legal residents to promote economic and social cohesion. But that requirement does not bar the member states from requiring social and cultural assimilation, he said.
And EU law does not expressly set temporal limits on member states to require integration - but they can't use legal residents' failure to comply as an excuse to deny benefits or revoke permanent-resident status, Szpunar said.
The adviser to the Luxembourg-based court added, however, that in the cases of "P" and "S" - who have both lived in the Netherlands for over a decade and have presumably developed deep ties to Dutch society - requiring them to pass an integration exam likely goes beyond what is considered proportionate under EU law.
Immigration officials should look beyond the letter of national law to the factual circumstances in such cases, Szpunar said in his opinion, which was not made available in English.
The adviser added that the fine assessed by Dutch authorities for failing to pass the integration test is also out of line with EU law.
Szpunar's opinion is not binding on the Court of Justice, which has begun its own deliberations in the case.
Member states' legal-residency requirements have taken a beating by the EU high court over the last year. Last month, the court ruled that Britian could not force a legal resident of the EU to apply for a visa every time she traveled from her home in Spain to visit her husband's family in the U.K.
And this past April, a European Court of Justice adviser blasted Germany for barring a Turkish woman from joining her legal-resident husband because an embassy official found her illiterate and therefore incapable of learning to speak and write basic German.