In 2001, the Portugese government decriminalised recreational drugs including heroin and cocaine in an attempt to reduce the number of hard drug users in the country. Eight years later, Claudia Hammond visited Lisbon to see whether the change in the law had been effective.
Lisbon was the European City of Culture in 1994
The first time I visited Lisbon was for a weekend break in 2001.
I was expecting to spend the weekend seeing the sights, taking trams and wandering the old streets looking at the blue and white tiles covering the buildings.
But unintentionally, I came face to face with the consequences of the rising rates of drug use.
One evening I was looking for a particular bar and seeing a sign in a broad, covered alleyway went to have a look. It was not the bar and as I turned a man blocked my exit and began backing me down the alleyway.
I screamed and screamed but no-one came. He reached for my bag and for a while we wrestled with it.
Then looking into his eyes, I saw that he was high on drugs and decided to let go.
Later the police were helpful and drove me round the streets, looking for him in bars.
The first thing muggers on drugs did, they told me wearily, was to go to a bar to sell your camera for cash, so that they could buy some more drugs.
Although I did not know it at the time, the Portuguese government already had its own plans to address the drug problem and the crime associated with it.
Not long afterwards they decriminalised every drug - cocaine, ecstasy, even heroin - all decriminalised.
They are still illegal, but a person caught with less than 10 days' supply is not considered a criminal, but a patient. Instead they appear before a Dissuasion Commission.
I was intrigued to see what this commission, which is so upfront about its aims, looks like.
In a concrete office block, I was shown into a room containing everyday office furniture.
In came a social worker and a psychologist dressed in jeans and shirts.
The whole idea is that even though the commission has the power to sentence someone to community service or even confiscate their driving licence, it looks and feels nothing like a court.
The panel assesses each person and decides whether they would benefit from going to a treatment centre.
The idea is to bring the subject of drugs into the open and that certainly seemed to be the case.
The first teenager they saw was happy to be interviewed on tape and to appear on the BBC using his own name.
He was super-confident and had hair shaved at the side with a tiny plait at the back.
He told me how he had been caught by the police smoking cannabis with his friends and more of the drug was found in his schoolbag.
Fears that Portugal would become a haven for drug tourists have not come true and the number of deaths from drugs has decreased
Because this was the second time he had been caught, he was sentenced to community service, which he thought was perfectly fair.
What had changed was that after talking to the Dissuasion Commission he was planning to cut down on his drug use.
But he told me quite openly in front of the panel that there was no way he had given up taking drugs completely.
The new system does mean that highly trained staff are spending 60% of their time dealing with people for cannabis possession, but if this means they can get to the people with drug addictions, then they believe it is worth it.
Before decriminalisation Portugal had 100,000 hard drug users in 2001
Previously people were so afraid of being arrested that they would not come forward for help.
One doctor told me patients would even ask him to unplug his intercom to his secretary for fear that someone might listen in on the consultation.
And the results? Fears that Portugal would become a haven for drug tourists have not come true and the number of deaths from drugs has decreased.
The secretary of state for health told me it has been a great success, with police figures suggesting that the use of every drug has either gone down or remained stable, apart from cocaine which has recently become fashionable.
In Portugal just 8.2% of people have tried cannabis at least once, compared with 42% in the U.S. But some argue that not enough figures are available to get the whole picture.
The most extraordinary thing for me was that wandering outside office blocks at lunchtime asking smokers on doorsteps what they thought about the drug policy, I could not find a single person who knew that all drugs had been decriminalised.
During my time in Lisbon I had not been intending to return to the alleyway where I was mugged, but walking along a street to an interview I saw a sign for a clothes shop.
Not wanting to miss a brief shopping opportunity I turned down the drive before realising exactly where I was.
But the seedy dark alleyway was now sunshine-filled with a pretty boutique on the left and a view over the red roofs of Lisbon on the right.
I cannot pretend that the clean-up of the old city is all down to the decriminalisation of drugs. Dealing is after all still done by criminal gangs.
But for me, that street at least is not a place to be afraid of any more.
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