The law forbids knowingly making false and defamatory statements that could lead to persecution of the accused person.

So for example, you can't accuse someone of being a rapist, for example, if you know that the accusation is not true.

Similarly, you can't accuse a politician of being corrupt just because you don't like them if you don't have any reason to believe that your accusation is true.

But it's absolutely allowed to publically insult a politician. And you also have the right to call a politician corrupt if you have a reason to believe that they are.

For example, I know that calling our former finance minister a corrupt self-serving asshole is not going to get me into trouble because there have been multiple news reports about him taking bribes.

I think for Americans it's just hard to believe that we don't protect made up lies as "free speech" around here.