The controversial arrest of German author Dogan Akhanli by Spanish authorities on an Interpol warrant issued by Turkey has triggered questions about the international policing agency’s modus operandi.

A dimly-lit street, rain glistening off the cobbles. A man in a long overcoat, collar turned up, takes a furtive look and a last drag of his cigarette before melting into the shadows. Okay, so maybe I’ve watched too many spy movies, but it’s the kind of scene that springs to mind when you hear or read the words International Criminal Police Organization (Interpol).

Early days

The concept of an international policing organization first popped up in April 1914, at the First International Congress of Judicial Police in Monaco. Leading criminal investigators were frustrated that criminals were increasingly able to evade capture by simply leaving the country, taking advantage of the burgeoning “progress of automobilism, even aviation.” A global approach to tackle the problem was needed: “The internationalism of crime should be opposed by the internationalism of repression.”

Read more: Spain releases Dogan Akhanli, German author detained on Turkish warrant

World War I threw a temporary spanner in the works, but in 1923 at the Second Judicial Police Congress, the International Criminal Police Commission – a forerunner of Interpol – was set up in Vienna. According to its founding statutes, it operated “to the strict exclusion of all matters having a political, religious or racial character.” It had no legal authority over member states, and existed merely to collect and catalog intelligence, and coordinate communication between different international police forces.

What does it do?

To keep Interpol as politically neutral as possible, its charter forbids it – or at least that’s the idea – from carrying out its own arrests or intervening in political, military, religious, or racial issues. Instead, the organization works in the background, collecting intelligence and coordinating and facilitating police efforts to combat anything from terrorism, war crimes and drug trafficking to child pornography and corruption.

Interpol, based in Lyon these days, has an annual budget of around 78 million euros ($91 million), most of which is provided through annual contributions by its 190 member countries. The entire staff, mostly international civil servants and police on loan from national police forces, is roughly 650 people.

One of Interpol’s key tools in fighting international crime is to issue color-coded notices to communicate information about crimes and criminals. The most powerful of these is the so-called red notice – which is the “closest instrument to an international arrest warrant in use today.” At the touch of a button, information about any given internationally sought criminal is disseminated to 190 police forces around the world. What at first glance appears to be an effective method to track down criminals in far-flung places is not without controversy, especially where authoritarian regimes are concerned. The European Commission, human rights group and others criticize that when authoritarian regimes request red notices against political opponents, Interpol is all too happy to oblige without necessarily carrying out full background checks. As a result, there have been several instances where dissidents, human-rights activists and journalists have reportedly been held for months in prisons before it is established that the charges against them are insubstantial or even bogus.

Read more: Interpol releases list of 173 potential IS bombers who could be in Europe

A key criticism leveled at Interpol is that there is no external scrutiny of its operations. The agency’s General Assembly that meets once a year is made up of policing experts – effectively people who are in the same line of work as their colleagues on the ground. Its majority-voting system means that even if a member state voices an objection to a case, its complaints can be ignored.

Interpol isn’t accountable to any outside court or body, and it is not obliged to share any data with anyone other than its own police members and its own appeals body. Its operations are deliberately opaque in the name of protecting law enforcement information. In a nutshell: If Interpol breaks its own rules, there is no one there to hold it accountable.

Contrast that with Europol, also an international organization for coordinating police work, but one founded on the European Community method. The European Parliament approves the budget and has a role in senior appointments, so there is parliamentary scrutiny on behalf of the citizens. The European Court of Justice has been given oversight of Europol, so there is judicial scrutiny as well.