I've answered that a thousand times. Make government smaller, there is therefore less for them to control. That is the only way. Government is made of people, people are corruptible. People with money will buy them You can't change that. So you make the amount that can be corrupted as small as possible.
If you grasp what I just said and grasp human nature. You will now convert to being a small government libertarian. It is irrefutable. Anything else will be self delusion.
Making government smaller only to reduce corruption doesn't reduce corruption at all. It actually makes it easier for government to be bought off because there are then fewer individuals to buy
Try reading what I actually wrote again and addressing that.
If ending corruption is what you want, make the penalty for said corruption so costly that any possibile benefit is overwhelmed. We can start by passing a Constitutional amendment forcing Congress to abide by the same laws as everyone else, pulling the exemptions they themselves have allowed for themselves out from under them.
Right, if you scare them, people with money won't try to use it to buy influence and politicians will become honest. What color is the sky in your world?