1. There is biblical mandate for self defense
The following is an excerpt from an article, to which I lost the citation- Sorry!
Exodus 22 gives some clues about God’s attitude toward self-defense: “If a thief is caught breaking in at night and is struck a fatal blow, the defender is not guilty of bloodshed; but if it happens after sunrise, the defender is guilty of bloodshed” (Exodus 22:2–3). Two basic principles taught in this text are the right to own private property and the right to defend that property. The full exercise of the right to self-defense, however, depended on the situation. No one should be too quick to use deadly force against another, even someone who means to do him harm. If someone was set upon by a thief in the middle of the night and, in the confusion of the moment the would-be thief was killed, the Law did not charge the homeowner with murder. But, if the thief was caught in the house during the day, when the homeowner was unlikely to be awoken from sleep, then the Law forbade the killing of the thief. Essentially, the Law said that homeowners shouldn’t be quick to kill or attack thieves in their home. Both situations could be considered self-defense, but deadly force was expected to be a last resort, used only in the event of a panicked “surprise attack” scenario where the homeowner is likely to be confused and disoriented. In the case of a nighttime attack, the Law granted the homeowner the benefit of the doubt that, apart from the darkness and confusion of the attack, he would not intentionally use lethal force against a thief. Even in the case of self-defense against a thief, a godly person was expected to try to restrain the assailant rather than immediately resort to killing him.
Paul engaged in self-defense on occasion, although non-violently. When he was about to be flogged by the Romans in Jerusalem, Paul quietly informed the centurion with the scourge that he, Paul, was a Roman citizen. The authorities were immediately alarmed and began to treat Paul differently, knowing they had violated Roman law by even putting him in chains. Paul had used a similar defense in Philippi—after he was flogged—in order to secure an official apology from those who had violated his rights (Acts 16:37–39).
The persistent widow in Jesus’ parable kept pounding on the judge’s door with the repeated plea, “Grant me justice against my adversary” (Luke 18:3). This widow was not about to give up and let her enemy take advantage of her; through the proper channels, she pursued self-defense.
I would also include in this category of self defense the many scriptures that speak to correcting slander, speaking truth, preserving the integrity of one’s name. Self defense is not just physical, but there is also justification for the self defense of our reputation
2. Civil Authorities
The Bible is also clear that it is God’s intention that civil authorities should act to defend their people and enforce justice.
For government is God’s servant for your good. But if you do wrong, be afraid, because it does not carry the sword for no reason. For government is God’s servant, an avenger that brings wrath on the one who does wrong. (Rom 13:4 CSB)
Be subject for the Lord’s sake to every human institution, whether it be to the emperor as supreme, or to governors as sent by him to punish those who do evil and to praise those who do good. (1Pe 2:13-14 ESV)
So, engaging in the forms of due process that our government affords us (e.g. reporting crimes) is something that we can, and should, pursue as Christians. Our God is a God of justice and so we should want to see justice brought as a means of reflecting His character.
For more on a biblical definition of justice, I’d highly recommend this sermon from Pastor Jared Mellinger https://www.sovereigngrace.com/sermons/sermon/2018-10-04/a-passion-for-biblical-justice
He also gives a bunch of reading resources in this sermon, which I would also commend.
Hope this helps bring some balance!