An undercover investigation by the city into online gun sales shows many private sellers are willing to sell to buyers who couldn't pass background checks.
Mayor Michael Bloomberg says an undercover investigation revealed 77 out of 125 private sellers were willing to make a sale with no questions asked.
Private sellers are not required to conduct background checks by law. However, if a seller has "reason to believe" a buyer can't pass, it's a felony to sell.
"Something like 40 percent of guns are sold privately and common sense says in this day and age the Internet is so easy to use, and has the ability people think to hide who they are and what they do, it makes common sense that the lot would. We certainly were able to go on and buy guns," Bloomberg said.
The investigation looked into 10 websites with 25,000 guns available for purchase.
Private sellers on Craigslist -- which prohibits the sale of firearms -- failed at the highest rate of 82 percent.