I want to make one thing clear. I am pro background check. (but keep reading) Yes. I am all for a system that ensures that only trustworthy capable people can purchase a firearm. So then why would I vote against it or ask someone to vote against it? Because the people who push hardest for the background checks would prefer that no one had a gun in the first place. This leaves me with a reasonable concern that the background check system I believe in will be abused to keep law abiding citizens from owning guns. Let me repeat that. This leaves me with a reasonable concern that the background check system I believe in will be abused to keep law abiding citizens from owning guns.
If for any reason you can't wrap your head around this please try this thought experiment. When you think about it, try not to assess right from wrong within opposing opinions but focus instead on the concept of allowing those of opposing opinions to make assumptions about another's intent.
Lets say conservatives decided to back down from all gay rights issues. Gay people can have everything they ever wanted. The only remaining concern the christian conservatives have is child rapists. So they decide the only rule they are going to have is gay people will have to do a background check to make sure they wont be targeting children. Now lets say this background check will be run by the christian conservatives. They will have the power to determine who is allowed to be gay based on the results of this check. Why would anyone in the LGBT community agree to this? Who would allow the people who like them the least to make the worst possible assumptions about them and determine their fate based on those assumptions. Is this making sense at all?
Now I know what you are thinking. Being gay doesn't mean wanting to rape children. You might even consider it offensive to insinuate that loving someone associates you with evil of any kind and I totally get that. But someone who buys a gun to protect their family might feel offended that anyone would equate it with wanting to do violence to anyone. Having a gun does not mean wanting to murder people.
The good news is: It is already illegal to rape children - or anyone for that matter just as it is illegal to shoot people. So we can bring to justice any people who break these rules.
If you can understand why our criminal justice system insures that everybody is innocent until proven guilty then you might just be able to understand why it is not a good idea to give anybody the power to determine someone is guilty of a crime that hasn't even been committed - Especially when that check is insisted upon by someone who thinks you are guilty just for requesting it.