The story of Roberts and Citizen’s United is actually somewhat interesting. The question initially presented to the court was simple - could Citizen’s United air a film critical of Hillary Clinton within the previously defined time period?
The vote was 5-4, and Roberts wrote the opinion, saying yes to only that narrow question. Kennedy wrote a concurrence suggesting the final, much wider ruling, which was taken up by the majority, with Roberts retroactively taking up this wider question presented sua sponte.
Souter announced his resignation while writing the dissent, and aired a lot of the court’s dirty laundry in it - he essentially suggested that Roberts manipulated the court’s process to create such a wide precedent.
