The texts showed that an officer spotted Crooks occupying a suspicious area more than an hour-and-a-half before the July 13 rally commenced at 6 p.m. Previously, Secret Service officials said Crooks was first spotted an hour before the rally—an amount of time many lawmakers already considered to be egregious at a presidential candidate’s rally.
Other texts obtained by the Times revealed that an officer spotted Crooks using a range finder about 20 minutes before the rally began and snapped photos of him—but didn’t approach him.
The strangest part of this is people expecting cops to do something that might plausibly put them in harms way
Modern cops are almost exclusively all lazy cowards at this point.
It has also been ruled repeatedly that police do not have a duty to protect you. There is no requirement that they risk their lives to keep you or anyone else from harm unless they have a "special relationship" with you, meaning you are in their custody. The cops were there to work the metal detectors and direct traffic. There's no way in hell they were going to take a bullet for Trump. That's the Secret Service's job.
Cops aren't trained in operational security. When you have a large event with multiple agencies and groups of people doing different things, then it's easy to blend in if you act like you know what you're doing. You can walk into almost any building if you throw on a high vis vest and carry a ladder. People will hold the door open for you and even let you into high security areas if you are smooth enough.
Yeah right Republican rallies and conventions are "gun free" zones where you no longer have your 2A rights, apparently. People carrying at these rallies would require Republicans to be logically consistent.
My educated guess is that they looked at him milling about outside the rally and assumed he was a Trump supporter based on his look and wouldn't be a problem.
As for the real answer, we'll have to wait for them to give a statement, but it'll likely be watered-down misinformation that paints police in the best light, so we'll probably never know for sure.
A button-down shirt/khakis and lanyard with a name badge often works, too, especially if you’re talking while using a Bluetooth headset and typing on a phone. People just assume you’re some low-level exec or IT support personnel, esp if your phone is on one of those tacky belt clips.