Yes, in theory communism is not Authoritarian. In Theory. I cannot think of practical examples of 'communism' that did not turn into oligarchies.
Ok, regarding the Paris Commune, to put it basically it was a period of time in the 1800's where the people of Paris declared the city independant from the rest of France, took control of all methods of distribution, equalised wages and put the worker's in control of factories, businesses, etc. It was incredibly successful and raised living standards, political and social rights until the french army came along, killed everybody, and regained control of Paris. You can find a longer description of the Paris commune at this link, which also has many more links at the bottom if you want further reading:
http://en.wikipedia.org/wiki/Paris_Commune
If you want another example of successful communism, a very good one is Spain during it's civil war. Again, living standards were raised along with social and political rights, methods of distribution, factories and businesses were nationalised and put under the workers' control, wages were equalised and it was successful (though there was a little internal debate between the anarchists and communists, it was minimal and was not really a major detriment to the new system or the war effort) until General Franco and his nationalist forces came along with Nazi and Fascist Italian support to crush the revolutionaries and regain control of Spain. More reading and links can be found here:
http://en.wikipedia.org/wiki/Anarchism_in_Spain (Anarchism and Communism in practice are exactly the same, the difference is in their writing; Anarchists do not recognise the class system, for instance.)
On the comment about Stalin, Stalin was not a communist, nor was his political system in the Soviet Union
anything even remotely resembling what is even written theoretically about communism. Stalin was not trying to achieve or experiment with communism, and this is where most uneducated people go wrong when they talk about communism, they equate it with psychotic dictatorship such as the Soviet Union, or North Korea. Though in reality both of these nations did not (still are not, in the case of North Korea) follow communist political theory or ideology. This becomes especially obvious ane evident when looking at the Soviet Union's advocacy of "Socialism In One Country", and their isolationist policies that run in direct conflict with communism, which is strictly internationalist, with no exceptions.
The problem with communism in this past century has never been with it's practice, or with it's theory. It has been with western government campaigns creating this illusion (with most people sadly believing it) that countries like North Korea and the USSR are/were great examples of communism in action, which is not just wrong to an incredible degree, but is simply laughable!
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Just a note, scandinavian countries such as Norway or Sweden are in no way shape or form socialist. They are simply mixed economies incorporating leftist ideas into capitalism to a more extreme degree than other nations, but they are not socialist nations, as they are not progressing towards communism.
Also, one thing that makes me laugh is the idea that capitalism is 'the perfect system' and that there will never be anything to replace it. Not only is that an incredibly naive thing to believe, it is the attitude the inhabitants of every system in history have taken. 500 years ago, nobody ever took the idea of capitalism seriously, and it was disregarded as a fool's idea as 'it could never work because we need divine royalty to give us direction', and we all know how that supposed 'self evident truth' turned out to be.
