EU member states must demonstrate a serious threat to public order and internal security to impose temporary border controls.

But government documents suggest member states are broadly allowed to deny people the right of free movement even when their own available statistics suggest that there is no major problem.

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Swedish police stopped almost 770,000 people in December alone, only 13 applied for asylum (Photo: EUobserver)

Earlier this year, the European Commission agreed for Austria, Denmark, Germany, Sweden and Norway to impose border controls for three months following ministerial letters to justify the blockades.

EUobserver has obtained letters from each of the member states, where they explain their reasons for upholding the border controls. Some admit there is no problem, while others offer scant data to support their arguments.

The commission has been pressing the states to phase out the controls without much success. The goal was to lift them all by the end of 2016.

Instead, the commission appears to be granting extensions despite the loose reasons provided to justify them.

In late January, EU commissioner for home affairs Dimitris Avramopoulos recommended the extra controls given the "unprecedented migratory pressure that Europe is facing".

But Norway said no one was refused entry and nobody had claimed asylum after having screened 157,000 people between December and early January this year at ferry connections with Denmark, Germany, and Sweden.

Norway's ministry of justice told the EU commission in early January that "no one has been refused entry following the border controls in this period."

It also noted that not a single person had applied for asylum, suggesting that the fear of so-called secondary movements of migrants venturing north through other EU states to Norway was no longer a "threat to public order and internal security".

The move poses larger questions on what then justifies the commission's recommendation only weeks later for Norway to uphold the controls.

Asked by EUobserver to comment, the commission has yet to respond.

Travelling asylum seekers

Asylum seekers and refugees travelling from Greece were among the initial reasons as to why border controls were first launched in 2015.

People arriving in Greece at that time would venture through the Western Balkans before reaching other EU member states in the hope of refuge.

The large numbers triggered panic among capitals as the commission scrambled to guarantee the future of the borderless Schengen area, comprised of 26 participating states.

Schengen is viewed as a major achievement of the European Union in terms of integration and the evolving single market.

Last year, the commission warned up to €18 billion annually could be lost if full border controls were to be re-established.

The commission says that any controls must be "necessary and proportionate."

But it is unclear how Norway's rationale for extending the border checks fits into the commission's definition of "necessary and proportionate," given the lack of evidence of any threat.

Austria, Denmark, Germany, Sweden

A similar lack of reasoning for prolonging the controls is also found in the letters sent by Austria, Denmark, Germany, and Sweden.

Austria was permitted to justify its demands despite noting that it cannot provide the EU commission with any of its own data.

"As in the previous notification, we cannot unfortunately give you data on the number of crossings and the number of persons controlled."

Instead, it broadly justifies the border controls by saying there is a steady rise in criminal suspects who also happen to have asylum status.

It also argues that the country has had to handle over 42,000 asylum applications last year alone and that Germany had either sent back or stopped over 13,000 people at the border with Austria over the same period.

More and more people also appear to be hopping onto freight trains to avoid detection in an effort to cross from Italy, Austria and into Germany.

"Over the last couple of weeks we've seen a diversion of flows away from Hungary to the Austrian-Slovakian border," notes the letter.

Denmark's government said it too wants to keep the controls despite the low number of irregular migrants arriving into the country.

Danish police had stopped around 215,500 people at its border with Germany between December and early January this year. Over 200 were told to go back and 147 applied for asylum.

"Although the number of irregular arrivals to Denmark has decreased, there are, at this stage, no grounds for phasing out or scaling down the border controls against Germany," notes the Danish letter.

Germany argued that controls need to continue because of internal security issues and that smugglers are adopting methods to evade the police.

Germany had been checking well over 100,000 every month between May and November last year.

But in December, it checked only around 14,000 after a Berlin Christmas lorry attack, which ended the lives of 12 people and left dozens injured. The suspect ended up taking a train to Italy where he was shot dead in Milan a few days later.

Sweden argues that its social and public services remain overstretched given the migration inflows from 2015.

Swedish police stopped almost 770,000 people in December alone. Police issued 231 removal decisions over the same period, while only 13 people applied for asylum.

"There are still no clear statistics available regarding delays for the general public and the commercial flow," noted the Swedish justice ministry.