It also seems to me that countries with higher wealth redistribution, like Scandinavian countries, have lower corruption.

I wonder about cause and effect here. I would trust the government more to redistribute wealth fairly if it weren't so very corrupt and incompetent.

What about making a jury trial for every law after the Parliament voted it, with 20 randomly selected citizen, held isolated from pressures like in normal jury trial, decide if the law goes through or not ?

I can think of several objections. Some laws are very complicated and require a lot of staff work by experts to formulate, and the jury won't be able to do a good job. Or did you want to require the jury to spend six months listening to testimony before delivering their verdict?

Do you mean an American or British-style jury, that requires unanimity? If so, you will reliably get hung juries on any controversial law.

There's a lot of laws that are time-sensitive. If the appropriations bills don't pass, the government shuts down. And we don't want to allow indefinite delays in restarting the government until the jury reaches consensus. (In America, there is probably 10% of the country who would reliably vote for shutting down the government, so you really cannot keep the country running if they can derail the jury.)