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This year Italy's carabinieri is 200 years old - it's older than the country itself. But why does Italy have two police forces and what is so special about this one?

I've always been puzzled by the fact that Italy has two police forces, although Italians don't seem to find it strange at all.

If you ask "why two?" they'll tell you, by way of unsatisfactory explanation, the polizia are the regular state police while the carabinieri are part of the army.

The real reason is a quirk of history.

The carabinieri are actually older than Italy itself. Their force was founded by Victor Emanuel I, Duke of Savoy and King of Sardinia almost half a century before modern Italy came into existence.

Their name comes from the carabina, the rifle they traditionally carried.

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Among the famous people they've arrested over the past two centuries, they can even boast one of Italy's founding fathers, Giuseppe Garibaldi - twice.

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When Italy was unified, the royal corps of carabinieri remained a nationwide military presence performing law enforcement duties so, in many ways, functioning as a duplicate police force.

In fact, you're just as likely to hear an Italian threaten to call the carabinieri as the polizia.

For one you dial 112, for the other 113 - but most Italians I've challenged don't know which is which, even though it says 112 on the side of the carabinieri's cars.

And just like the police, they're loved and loathed: hailed for acts of courage, condemned for excessive violence.

But the one thing they're best known for is being the national butt of politically incorrect jokes: where once the English featured an Irishman, the Italians have a carabiniere.

Regularly lampooned in films and on TV, their archive of historical regulations doesn't help shake the comic image.

For example, their strict moustache, beard and sideburn protocol went from none, to some, to "a facial bush is fine as long as it's trimmed".

At a certain point, there was one directive allowing only the highest ranks to sport moustaches, and another banning them altogether. Some might call that "carabinieri logic".

Image copyright Carabinieri

Joking aside, it's historically been a lonely career for two reasons: carabinieri weren't allowed to serve in their home region and were subject to very restrictive rules regarding marriage.

Even today, echoes of those old regulations still exist. They can't return to work in their region of origin until they've served for at least eight years.

That's why on long-distance train routes you'll so often find yourself sharing a carriage with a young, off-duty carabiniere going home or returning from leave.

In the sleepy satellite town of Pianoro near Bologna, my local carabinieri are a friendly bunch.

One of them, who prefers not to be named, talks enthusiastically about the job.

He always wanted to be a carabiniere and points proudly at the little stars on his collar: "The police don't have these because they're a civil service. We're a military corps. We have a very different kind of training."

I ask him what's different and he explains that it's all in their relationship with the citizens.

"Even in the smallest mountain and rural communities you'll find one of our stations," he boasts.

There are 4,605 of them throughout Italy and he says their role is to be there for the locals.

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"They rely on us. When there's an earthquake, a flood or any kind of disaster, we're the ones who provide immediate support," he says.

I know from his accent that he's not from the north. I tell him I've never met a carabiniere who wasn't from the south.

He nods. "It's true, most of us are. I'd say about 70% of the entire force. Not just the south, four regions in particular: Sicily, Campania, Calabria and Puglia. At this station, all of us but one are from Campania."

He says it's no coincidence that so many carabinieri come from precisely the same four regions as Italy's four major mafia organisations.

"There are two reasons why you become a carabiniere", he tells me, "the main one is a sense of justice and 'rivalsa' (retaliation or payback)."

When you grow up in that environment, he explains, you have to choose sides. "Becoming a carabiniere is like making a statement to say 'I choose legality'."

Image copyright AFP Image caption Carabinieri officers flank Ndrangheta crime syndicate boss, Pasquale Condello, during his arrest in 2008

The second reason is simply that it's a profession which gives you job security.

The hardest thing, he admits, is being so far away from your family and your land.

But he says it's worth it: "I've been in the force for 17 years and, yes, I'd like to be transferred back down one day, but I'm happy here for now."

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