I suggest that we reform the process by which the representatives are selected, such that we can find some that can be trusted.
Sorry, but quite hopeless. The system we have is that they are (usually) selected by local parties whose self interest is in finding someone fairly reliable.
After that is we elect them, and they prove unreliable, we do not re-elect. No system can provide the guarantees you want.
If you look at the New Labour gang, they were very probably all reliable when first selected - but power corrupts. They fell into the eventual state of evil.
Perhaps the right thing would be to ban anybody being re-elected more than twice, but that brings in its own severe difficulties.