I have serious worries that my homeland was the most affected one
Physicsnut has posted the fresh British Channel 4 video which is a result of investigative journalism par excellence, I believe. As far as I can say, the "doubly scholarly" named organization was shown to be a bunch of criminals who should be arrested for a very long time.
Steve Bannon has been among the key founders and whether they have violated the law in the U.S. is a matter of accusations now – 50 million people's Facebook data could have been abused. But Channel 4 has sent a fake "client" to Cambridge Analytica and they recorded the offer. What the "client" was offered included fake discrediting materials against the political foes, using pretty Ukrainian prostitutes hired for that special purpose; basically fake videos proving corruption because Cambridge Analytica's representative makes an offer that almost no one can refuse (I would refuse any offer!); and many other things.
Some of these tactics surely are illegal in many countries right now.
Cambridge Analytica studies each potential swing voters (or many of them) and finds the special kind of a message that may bring the individual voter to the desired direction – and he's served the corresponding online material. Steve Bannon was a key co-founder of Cambridge Analytica but that clearly isn't enough to make the organization ethical in my eyes.
The organization has boasted to have made a difference in several countries where you expect voters to be borderline morons – such as Kenya, Nigeria, and indeed, the Czech Republic (and India and Argentina). Also, they have bragged that they recently concluded a very successful "project in an Eastern European country".
I am not sure and I don't have a hard proof but I think it's more likely than not that the previous sentence talks about Czechia, too. They are using "subcontractors" so it's not even clear that they're in the country. I know who the Czech subcontractors would be. Marek Prchal, the P.R. expert praised for the success of the populist oligarch Babiš and his ANO movement (that won the October 2017 elections with 30%), and Jakub Horák, the P.R. expert who prepared the campaign for the Pirates (who scored an impressive 10%), are the two top candidates.
The guy from Cambridge Analytica has openly said that they want the elections to be all about emotions, no facts, and they investigate how low they can stoop. Who stoops lower, wins, we learn. OK, I don't know whether an organization with this publicly revealed goal is illegal at this moment but I surely think it should be illegal. If an organization is allowed, its demonstrably stated purpose shouldn't be to lower the political culture in a country.
Concerning Czechia, I am not quite sure what kind of dirty tricks and fake discrediting materials have been used. I don't remember any. Babiš – and, to some extent, even Zeman – won their recent elections by the old-fashioned dumb populism and superficial, general, hostile comments against the opponents and/or cheap material promises. Well, it's plausible that Prchal needed to be advised by Britons that tons of people want to be told "everyone is a thief" every day, because millions of Czechs are just incredibly jealous, so Babiš has been saying these things every day.
It's plausible that some "data mining" may help to some extent. But Babiš couldn't have won without 1.5 million of the brain-dead voters who are ready to buy the demagogic stuff of the most primitive and transparent type, without whole layers of jealous filth that has no idea about the mechanisms that make the society work. Citizens "doughnuts" whose political thinking is at the level of Kenya and Nigeria, indeed. And he couldn't have won without the unethical decision to actually exploit these voters despicable traits.
However, maybe, Babiš has paid them to find some materials that haven't quite been used yet. For example, Babiš started his dirty tricks to get rid of Mr Michal Murín, the boss of GIBS (police against policemen). One of the findings is that Murín has been to a brothel. It's totally legal for a GIBS' boss to go to a brothel in Czechia, of course, but I guess that Babiš will want to use it at some moment, anyway. Maybe this data was provided by Cambridge Analytica, too.
At any rate, I think that there should be an extensive discussion among the lawyers, lawmakers, and pundits who should identify what existing laws they have violated, what should remain legal, and what exactly should be made illegal. I think that if Cambridge Analytica has used the user data from a de facto monopoly social network such as Facebook for some candidates only, it's just unacceptable.
Also, if such data are used by a candidate or a party at all, I believe that such usage of the data would have to be transparent. If one candidate has the access to the Facebook personal data, others should have the access, too, and so on. Similar rules must be adopted to prevent some dirty candidates from de facto buying their political power through similar organizations and dirty tricks.
There are lots of technicalities concerning possible claims of innocence. For example, Cambridge Analytica reacted by saying that the interview with the Channel 4 "client" included offers of illegal and unethical tactics because the company wanted to check whether the client would say No. So Cambridge Analytica claims to have acted as an agent provocateur against the "client". Well, I think that private entities shouldn't be allowed to act as agent provocateurs – they shouldn't be able to use this excuse to reclaim innocence.
If some clearly unethical tactics have helped Trump or Brexit, then I would be disappointed, of course. But here one must appreciate that the case of Trump and Brexit remains in the stage of accusations; while the cases of Nigeria, Kenya, Czechia etc. have been more or proven by confession.
You may also see what is the nationality of those that are distorting the results of elections in the world. It's not the Russians. It's e.g. a profit-making British organization working with former American and Israeli agents, we learned. Quite a different picture of the influences in the world.
Of course, if someone starts to be arrested etc., deep enough investigation should be made whether others have used similar tools because it's plausible that most viable candidates across the world use such dirty tricks.