Switzerland is concervative in some part of the country. It's not like the US but the country has a division based on countryside and cities, cities being more liberal.

What made a change in the policy is that Switzerland had at the end of the 80's the first and the second most important open scene in Europe. People came from all the country and even further to use drugs mostly opioid. People were using next to the Federal palace, home of the Parlament.

They had to do something and decided to have a liberal, progressive policy to help people instead of criminalizing.

But, we have multiple parameters to take in account. The first, it was at the end of the 80's and the beginning of the 90's. The population composition was different at this time. If you were not swiss, the chance to be deported was high.

Another factor is cultural. In the swiss culture, powerty doesn't exist. People are wealthy. The really is different so Switzerland literally hides the poor and powerty. It's similar to put everything under the carpet so everything is nice from the outside. The fact to see in parks and the nearby streets drug users day and night wasn't a good think. The liberal policy match's the fact that powerty has to be hidden.

It's not only to be good or to do something good. Switzerland did horrible thing for the same reason like deporting children of poor families or single parent.

If people have an interest on the topic, I share two albums on imgur to see how it looked like. Both are NSFW!

Open scene in Bern, it was the second most important in Europe.

The open scene in Zürich was the most important across Europe.