The Affair - S1-E4
Continuity mistake: When the stepson arrives at the villa, he makes his way to the front door, shoving aside reporters. Between his POV and the next shot, the same reporters move away in different ways, with different timing. (00:03:10)
The Stripper - S1-E3
Continuity mistake: In the (deliberately poorly lit) scene where Doug's friend hurts her hand, look at the moment when she picks up the shard of glass; it goes nowhere near the area where the bandage appears later. (00:26:10)
The Stripper - S1-E3
Continuity mistake: Matlock walks by mistake inside the dressing room. Two girls with their bare backs to the camera stare back at him. We see Matlock close the door a moment later, and there's just a very much clothed girl where the two naked ladies would have been. (00:21:15)
The Stripper - S1-E3
Continuity mistake: When Matlock approaches the widow to "convey his condolences," she is standing still, but the natural light on her changes between shots. (00:14:35)
The Stripper - S1-E3
Continuity mistake: When Ben and Charlene Matlock visit the precinct and give The Gift to the proud new daddy, Ben teases him, saying that it's so that the boy will dress better than his father. The guy acknowledges the joke, pointing at Matlock in a friendly way. Nothing in his hand, then all of a sudden he is holding a cigar. (00:06:00)
The Stripper - S1-E3
Continuity mistake: Carla's kid at the beginning of the episode asks her to stay with her and sleep on the couch, "Please, Mum, please?" Notice the book in his hand change position between shots. (00:02:20)
Plot hole: The resolution of the case hinges on the fact that the culprit would be compelled by The Witness (whom they bribed, but who double-crossed them) to visit their stake-out apartment to try to dispose of their bloodied clothes. However, The Witness didn't and couldn't possibly know about that apartment. The murderer tried to prevent a non-existent threat that nobody made and did not worry at all about the other, very much more likely evidence and testimony The Witness provides - if The Witness was going to trick them to begin with, it makes no sense that they didn't just record the conversation, for once. The culprit does not even contemplate that possibility.
Continuity mistake: When The Judge is on the stand and Matlock approaches him to start his examination, Andy Griffith's right hand is on/off the railing, depending on the camera angle. (00:39:40)
Continuity mistake: Charlene comes back to the office after subpoenaing Piper Laurie. Ben is at his desk writing some notes. However, the pad turns 90° as the camera angles alternate. (00:19:50)
Diary of a Perfect Murder - S1-E1
Continuity mistake: When Lockwood is on the stand, Matlock asks him if he is aware of ties with the "American Unified Finance Corporation." As he spells out the name of the company, he moves the side of his hand along the railing in small steps. However, there is a reverse shot in the middle of it where his arm is still and positioned at a different height. (01:24:20)
Diary of a Perfect Murder - S1-E1
Continuity mistake: When Paul Lockwood catches Charlene Matlock and the others at his plant and tells them they are trespassing, Ben eventually says, "Let's go." Lori Lethin pulls away from Andy Griffith two separate times in that shot and the next. (01:19:55)
Diary of a Perfect Murder - S1-E1
Continuity mistake: When Matlock starts implying that Mr. Banning is the one that tipped The Scandal reporters about his client, he clutches the stand with both hands and shuffles back and forth. As the line "frequently pay people to alert them" is spoken, transitioning to a different camera angle, he is all of a sudden no longer clinging to the railing corner. (01:11:15)
Diary of a Perfect Murder - S1-E1
Continuity mistake: When Matlock pretends he's done with Banning, the hotel desk clerk, he walks away from him. Richard Lineback has his hands in his lap in two different ways in the two separate shots, just beginning to stand twice in a row. (01:10:35)
Diary of a Perfect Murder - S1-E1
Continuity mistake: Matlock questions Mrs. Harris at the stand; Andy Griffith keeps switching between a hand in his pants pocket and a hand on the jacket over his hip. (01:06:40)
Diary of a Perfect Murder - S1-E1
Continuity mistake: Prosecutor Burton Hawkins shows People Exhibit B (the murder weapon), doing a fancy twirl, keeping his arm outstretched in the wide shot. His spin concludes in a narrower camera angle; this time, his arm is down. (01:04:15)
Diary of a Perfect Murder - S1-E1
Character mistake: Prosecutor "Death Row" Hawkins finishes speaking with prospective jury member Mr. Cooper and tags in The Defense attorney, saying, "Mr. Matlock, your witness." Naturally, Cooper is not a witness of anything; they are selecting the jury.
Factual error: This takes place in Atlanta, but in the scene where Tyler pulls up to Matlock and The Professor on the bench, there are California-style palm trees visible in the background. (00:18:35)
Answer: I did not see this episode, but YES. Both prosecution and defense lawyers use investigators to search for and uncover evidence that is legally admissible.