system
Given the following post, respond as if you're commenting on Reddit:
human
Why are so many people against background checks for purchasing weapons?
gpt
We already have background checks when you buy from a dealer. The issue is background checks for private sales. It would make buying or selling a firearm difficult for private citizens. If you had a friend who wanted to buy a gun from you, then you would have to go to a dealer to facilitate the transaction since regular people don't have access to the National Crime Information System. It wouldn't be fair for the dealer to be forced to use his manpower, Internet connection, and subscription to NCIS for free, so they would be able to charge a fee. 

The only people this would effect are the law abiding citizens, because the criminals won't comply with the law.