All federal agent are required to carry his service firearms (Not just their sidearm) even when they are off duty, they don't do what normal cop do, which is go down to the armoury to check in/out their weapon, only if they need special weapon (such as grenade launcher and/or assault rifle) And if you are a SWAT member with in the Feds (Such as FBI HRT or BATF SWAT) you are required to carry your standard weapon (AR, Pistol and anything you qualified) at all time in car or in person even if you are off duty.
So if I am a FBI and I cam qualified for shotgun and pistol, I will have my shotgun in my boot of my car and my sidearm on me everywhere and anytime, on or off duty.
The problem is not with the FBI, or rather not just with the FBI but all Federal Agency currently in the United States. The Fed is lacking a clear direction/communication with local law enforcement.
On the other hand, Local LEA unwilling to share jurisdiction and suspicion on the Fed are another issue that cannot be ignored.
Take Mass Shooting incident as an example. What the FBI can do is gather data (or in the field we called "Passive Intelligence") provided by BATF or other Federal/Local LEA and put high risk individual/organisation into a watch list, and like its name suggested, they can only watch, they can't talk to or question these individual or organisation, nor do the fed able to arrest or even apply for a search warrant to these individual/organisation to find evidence so they can be arrested. Because FBI do not have the jurisdiction to do so unless that individual/organisation crossed the line and becoming a terrorist or terrorist organisation, or literally cross the state line and committed a crime, then they will become FBI jurisdiction.
The best the FBI can do is to give Local LEA a All Point Bulletin (APB) if he/she is deemed dangerous or a Service Brief which go by every month and raise point on these subject, and to further the complication, FBI is not allow to share sensitive information to Local LEA which mean if the person is not deemed dangerous, the most FBI can tell local agency is that "Be on look out with this guy, he is about to do something bad in your state/jurisdiction" on the weekly briefing.
Local LEA, however, do not have the intelligence resource the federal government have, but they are the one that have to do most of the work. On the other hand, most of the time if and when there is a federal briefing, the most they will get is a list of people in your state/city you need to watch out for, and for what? They don't know, and the Fed won't tell them. And most of these are hit and missed (It could be just be a normal guy buying some item that cross the Fed threshold and have no idea what he is doing, or it can be the next ted bundy gearing up for the kill). At the end of the day, Local LEA don't have enough resource to put a detail investigation on everyone in their list, and that is how these people get away with being noticed. And when these people committed their crime the Fed predicted, you will see they are in their list and nothing is being done by the Fed and Local LEA.
This, is the problem and unless we can change how Federal/State/Local law enforcement works, it will always be the same.
