I taught forensics for years. This does not mean I am an expert. What it does mean is that I spent 90 minutes preparing each lesson which was itself close to an hour long. That is 190 lessons in a year, or close to 500 hours a year spent on this subject for years. If you really want to study a topic you should try teaching it. You study it, you teach it, then you must grade 30+ papers on the topic, and then you do it all over again the next year and the next year.
There are some really excellent fictional dramatizations of what is possible. Dekter describes a blood spatter analyst and all the things that can be determined by simply looking at blood spatter.
Bones demonstrates state of the art scientific methods, primarily showing you want can be determined by looking at the bones, but also at trace evidence and doing recreations of the event.
Lie to Me is based on the research of a scientist into micro expressions and those who study body language.
A whole host of cops and robbers shows incorporate various techniques used in questioning and interrogating people.
The problem that most if not all the shows have is they condense what might take a month into a 40 minute show and they assume you have the best and the brightest working on the case.
There are probably a thousand campaign events going on the country this month, and you would never expect the best and the brightest to be at all of them. But you would expect that those who are protecting a former president and someone campaigning for the presidency of the US would be the best and the brightest.
There are people trained in spotting suspicious behavior. What you and I cannot do they are like savants. You can be trained in this profession and it take about six months to be very competent and a couple of years to be very proficient at this.
There are others who are trained snipers and trained at stopping snipers. They know exactly what they are looking for and will spot it when you and I would miss it. This takes six weeks to become aware of what to look for, a year to become competent, a couple of years to become proficient, and a few more years to become a real expert.
You would think that the few people on Trump's team with these assignments would be at the expert level.
Dan Bongino who would also have been at the expert level since he worked for Secret Service protecting presidents for years described this shooting, not as something that would have been very difficult to stop but perhaps the easiest and the most obvious attack to stop. We are not talking about a guy a kilometer away making a shot, we are talking about a guy in plain view 130 yards away, on a white roof where no one was supposed to be with a rifle. This is not Ronald Reagan getting shot by some guy in a crowd with a pistol hidden. This is a guy in plain view crawling on a roof with a rifle with people in the crowd pointing him out and the police having seen him. There is no excuse for Trump to have still been on the stage while this threat was in plain sight. The sniper team is in constant communication with Trump's security detail. They saw this threat 40 seconds before he shot. No excuse for Trump still being there.