To take a honest look at the Bible’s approach to government we have a few obvious high level principles that outline an approach to the political .
In the Old Testament God directly ruled an often disobedient Monarchies, not becauseGod wanted to have monarchies but initially because the people wanted a King. In any case that was the kind of government’s people had at the time and a King was thought needed to defend against other Kings and peoples.
In The New Testament God no longer directly rules a government but Jesus clearly divided his spiritual kingdom from the political kingdom and sidestepped political traps about taxes and rebellion when questioned by zealots and officials alike.
When the Apostles were then spreading the gospel they wrote nothing about politics as their mind we’re dealing with subjects much higher than worldly affairs, maintaining Christ’s example and keeping Christ as the only centre in all thinking and discussion. Part of this discussion includes full submission to all authorities, whether good or evil.
Indirectly however there are obvious breaks with both the Old Testament believers and New Testament believers who are forced to break the law and protest against laws that are under God unlawful. A couple examples are Daniel in the Lions den and the churches command to preach the gospel to all nations. Of course if a nation outlawed preaching the gospel, then that law would be broken because it is unlawful to a higher law.
So if suppressing free speech includes suppressing Biblical doctrines from being preached, free speech must be maintained against the law of that society, even if that leads to imprisonment.
However apart from these isolated diversions from the otherwise general command to submit to all authorities, it seems the Bible leaves political subjects to the world and not the church. It also is obvious we are part of the world, so as a citizen (not as a Christian) we may hold any political view we like and if legal in the country, protest or not based on our own freedom and will, so long as we are not being rude and offensive to our neighbors who we claim to love. These is the other obligation, loving our neighbors.
We should also have some gratitude for civil secular worldly laws no matter how corrupt they are because it is Gods law in general that they serve to punish murderers and thieves. If it was not for the Old Testament still maintaining a shape within secular powers as provided by God, we would certainly all be robbed and killed by our dear neighbors among us. The law restrains human nature in its practical outcomes while increasing the evil desires among those trapped under it. Only in Christ is one freed from the law and the politics itself, as politics is basically neighbors hating each other as they express themselves.
Even so, getting into the mud of politics is in some ways necessary as citizens as we are all involved.