Heaven forbid if you or anyone remotely connected to you goes to prison in the wizarding world. It would be more accurate to just specify that you don’t want them to go to Azkaban, since that’s the only wizard prison. And that’s the problem here. Azkaban is in the middle of the ocean, so there’s no possible escape or even likely chance of visitation. And it’s policed by Dementors, fear and depression incarnate. Even being around one makes someone physically ill and depressed, and reliving your worst memories (another side effect of their aura) can be intense enough for someone to pass out, in the case of Harry’s first encounter with one. That’s not the worst of it. Dementors can suck out souls, and relish doing so. Fully doing it kills someone, but even a passing attempt can mess someone up. And that’s what everyone sentenced to prison has to deal with. Take the case of Sirius Black. He was falsely convicted of murder (spoilers, I suppose?) and spent years in Azkaban, before breaking out. He wasn’t even released or acquitted, and it seems like breaking out of prison is the only way to escape Azkaban that works. And after he got out, Sirius was seriously unhinged for quite a while, despite being one of the good guys. People like Bellatrix Lestrange are more typical examples of what results from being repeatedly sent to a prison that does its best to make you insane. Prison in the wizarding world isn’t for rehabilitation in the slightest; it seems like the worst thing they can do to someone who breaks the law. To many wizards and witches in the book series, death would be preferable.
If being slipped potions or being dragged off to a hellish prison weren’t enough paranoia fuel for you, there’s also the infamous Polyjuice potion. One dose is only enough for about an hour, as we saw in the second book in the Harry Potter series. However, there’s little keeping someone from continually dosing up to keep up the charade, as we saw in Harry Potter and the Goblet of Fire. Nightmarishly, in order to do so, you’d need to hold the person being impersonated hostage, in order to keep up the supply of potion. It requires a component of them, a piece of their hair, so even if you shaved the poor person beforehand, you’d eventually run out. We saw one poor professor imprisoned for a full year, kept barely alive, so that a Death Eater could take his place. And the worst part is, if someone has studied how to act, you would never know that you were around an impersonator. Functionally, the Polyjuice potion turns someone into someone else on every level except the mental, and even then, we don’t know if there are ways to verify someone’s identity using this. It certainly wasn’t used in the books.