In free democracies, politicians are elected representatives, not rulers. They are accountable to voters through regular elections. Power is distributed across multiple branches/institutions. Citizens have protected rights and freedoms. Politicians can be voted out or recalled. Laws apply equally to politicians and citizens.

In practice, there's always a slippery slope, can wealthy people integrate themselves in that power structure, lobbying, media control, strength of checks and balances, level of corruption/transparency, etc. But when that slips, we stop calling it a free democracy, and it becomes an oligarchy, or a plutocracy, or an illiberal democracy.