In theory it might prevent access to other buildings, but equally often the card readers are around doors of mostly standard glass or near internal windows of the same.
So if that’s the motivation, it doesn’t seem like a particularly effective mitigation
Also in what world is a badge reader going to contain an armed gunman unless the walls, floors, doors, and windows are also bulletproof??
(Triangle shirtwaist fire resulted in 146 dead)
Bullets aren't universal door openers, and shooting your way through one lock doesn't magically unlock the next one.
I’m not saying that to diminish the value of the actual solution, but what the people want is literally something to make them feel better about a situation that is mostly out of their control.
Someone showed up to their workplace with a fucking gun. And now they have to go there every day, and hope it doesn’t happen again. They want and need the theater.
Where people actually care about physical security, they develop things that do actually work; and often are so unobtrusive you never realize they're there.
Security theater necessitates that it be showy and in your face.
Will my front door stop someone robbing my house if they want to? No: I have sidelight windows you could just smash them and come through.
But the one time a house I was in got robbed, it was because we left the front door open and went out.
Which is odd if you think about it right? Statistically an open front door rather implies someone is home, not away so it's a terrible targeting priority - but our house was targeted and not say, our neighbors who also wouldn't have been home that day.
People are quick to claim security theater, talk about threat models, but equally ignore them anyway.
I knew someone years and years ago who worked as an assistant to lawyers. The firm had a second office in the state capital, turns out someone was walking in and stealing laptops. I think they had done it three times the last I had heard.
Lawyer laptops going missing is a problem. I don’t know how they ended up fixing that.
It shouldn't be. If there was a particular profession that I would expect to properly secure their devices lawyers would be near the top of the list.
(While at it, I once worked on an access control system. It was aeons ago; the system ran under OS/2. We installed it on a factory. It worked well, until we ran it in demo mode under production load, that is, the stream of morning shift turnstile registration events. The DB melted. I solved the problem trivially: I noticed that the DB was installed on a FAT volume for unknown reasons, so I moved it to an HPFS volume, and increased the RAM cache for the disk to maximum. Everything worked without a hitch then.)
A shooter can get a badge. Most partitions aren't bulletproof (and probably don't have security film), and a shooter doesn't fear getting a cut on some tempered glass.
The thing that would be effective is 24/7 security monitoring with a building lockdown and reinforced entrances/partitions. Of course, the victims whose badges were disabled during lockdown will sue.
So instead, just install badge readers and say that "something was done".
We learned this during a funny situation when a customer sent us the wrong question set for vendors. We were asked to clarify our plans for example for an armed intrusion by an armed, hostile force to seize protected assets from us. After some discussion, we answered the equivalent of "Uh Sir. This is a software company. We would surrender and try to call the cops".
During some laughter from the customer they told us, the only part missing from that answer was the durability rating of our safes and secure storages for assets, of which we had none, because they just had to last until cops or reinforcements arrived. That was a silly day.
Ask the people of Uvalde, TX about that security model.
Killing a boss with a keycard that opens everything might not just be possible but also preferable. Fuck you Tom, you made me work through memaw’s funeral