Would they? what if the network is being controlled by the goverenment it self? 51% attack would be an easy way for them to manipulate the results... Unless they use a 3rd party blockchain like ethereum. There is nothing stopping them to manipulate the results.
Ethereum's blockchain in no shape or form offers any decentralization, especially with how you only need to make sure you catch Vitalik and you're pretty much good to go as government.
Ethereum has rolled back the chain already to save investor funds, and that with a minority agreement! In other words, Ethereum is pretty much the last blockchain you would want to use for these purposes, especially if you take into consideration that Vitalik recently admitted to write a fork in case he's forced to do so. It's a complete lunatic.
Voting itself is and will always be prone to some extent of manipulation, even on the most decentralized network as the one from Bitcoin.