Studies have shown that each year over 2k guns are sold to individuals on watch lists. Since just being on the watch list doesn’t disqualify you from purchasing a firearm all the FBI can do is flag the record for review of increased surveillance or monitoring. Unless you are going to support additional questioning or interviews with field agents prior to the approval then it is kind of meaningless. I for one would fully support this occurring but I also feel fairly sure people would oppose having someone questioned because they are on a watchlist.
As to whether it is odd that people on the watch lists are involved in mass shootings why would that be? They made those lists for a reason so the fact that someone people were concerned about potentially being violent turning out to be violent doesn’t surprise me at all. In fact I’m more surprised when it’s an individual not on the watch list.
What kind of watch list are you talking about? The “no fly” list? Some politicians have pushed for those on the no fly list to be barred from gun purchases, but that’s ensnarled innocent people. There are people on that list solely because they have a similar name as someone who SHOULD be on the list, or a clerical error has been made. And once you’re on the list, it’s almost impossible to get off.
Ted Kennedy used to be caught up in this, as well as Rep. John Lewis. Even with their political standing they kept being stopped. I know two people who get flagged every time they fly, because their names are similar to names of people legitimately there. Both have been denied entry to flights on a few occasions, delayed by hours on others.