The Citizens United ruling by the Supreme Court grants personhood to corporations and thereby deems a corporation is like a person and has freedom of speech. They further state that since they have freedom of speech, they can therefore give unlimited funds to support the political interest of their choice without disclosing the source of the funding. This allows multi-national corporations to to fund our political system with foreign money, without disclosure.
This gives the super-rich and corporations an unfair advantage over the people for funding politicians.