All court cases are held in public, so if you are interested in the full evidence, etc, you can attend the hearing in person. Moreover, all cases are recorded, so you can request a transcript of the whole process. Most judicial decisions however begin by a summary of the facts and the laws that were in question.

Once you get a decision, you can fix it. You appeal it. If the court was wrong, then the higher court is likely to overturn it.

The point about being able to read the judicial decision is that if the judge applied the law incorrectly, whether because he was corrupted, because he did not like the defendant or anything, if you are a trained lawyer, you can see that the law was applied incorrectly, so you appeal it. If that appeal is successful, the judge below would loose a huge amount of reputation, especially if it was blatantly obvious that he applied the law incorrectly. So no judge would do it. They are paid very handsomely. They probably practised as lawyers before becoming a judge so made quite a bit and therefore they have nothing to gain and everything to loose if they accept being corrupted.