Offhand, the old, "FBI" series starring Efrem Zimbalist, Jr. comes to mind. You asked why. It just seemed more plausible than most and showed the Bureau as it probably was then, more or less. I think they had an FBI advisor, who was careful Not to Embarrass The Bureau!
One of the less realistic, although I (sort of) enjoy it is the current, "Hawaii Five-O". I can't stand the short jerk but like Grace Park and mourn the demise of Lauren German's role. The Navy Intelligence officer that McGarrett likes is okay, pretty cute. But McGarrett's tattoo is out of place. And they need to have done with Wo Fat or whatever the villain's name is and move on to other crooks.
"The Mentalist" has also grown on me. I dislike the hero's morals and style. But I like his harried female boss, and the Korean (?) guy, Cho, is okay. A bit too Joe Friday with his just-the-facts-ma'am style. But he's a good detective. (California Bureau of Investigation)
"Criminal Minds" is sometimes a little too over the top for me, and I dislike three characters, who are simply unrealistic. One is there mainly for PC reasons, and the other two are clowns in such roles. But Aaron Hotchner (played by Thomas Gibson) and Agent Rossi (Joe Mantegna) are among the best TV cops, ever, and are quite plausible in their roles. Hotchner is a bit too tightly strung, but by TV standards, good. The female agents are good. I especially like JJ. (Jennifer Jarreau.) I miss Emily. Her replacement is played by a superb actress, Jeanne Tripplehorn. But the character is getting a bit old for a major eye candy role. I liked her very much in "Basic Instinct". But it was filmed about 1992!
Last week's episode of, "Blue Bloods" disturbed me considerably, and I suspect that Tom Selleck wasn't too thrilled at what the script forced him to do. He seems less of a Hollywood liberal than are most actors. I can't discuss this episode due to board rules, but the theme stuck in my craw. (Whatever a "craw" actually is, the show stuck in mine.
)
