Every three years, the Washington Metro Police Department (MPD) will send out forms requiring gun owners to verify that they "still live in the District and... still have your firearm." The penalties for not complying with re-registration range from "a $13 fee to a $1,000 fine and one year in jail."
When Senator Joe Manchin (D-WV) pushed universal background checks earlier in the year, Breitbart News warned that the federal government would have to create a gun registry to make Manchin's plan work. The government would have to know where every gun is and who owns it in order to know whether people are submitting to background checks or selling privately.
Similarly, the D.C. universal background check policy has led to a gun registration program for just this purpose.