how to pick out the killer in coldcase?

"2)when someone is introduced in a flashback or a scene with no apparent reason,it can be a clue to the killer: for example, jimmy bar tram in justice (the two flashbacks with his sister or ed matheson at the hospital in stalker. In the CSi series this happens more often.."

As something to possibly add to that, if an actor appears to have a small and unimportant part compared to how famous and/or acclaimed they are.

I remember somebody saying once about Mindhunters: You don't hire somebody as good as John Billingsley just to have him be the records clerk (or something) so something had to have been going on there.

I also saw somebody point out that the killer is often the first person the detectives talk to.

I've figured out that a majority of the killers are introduced on or around the 25 minute mark (in a show aired with commercials, so maybe the 20 minute mark without?). The killer has definitely been introduced before the 3rd commercial break, and the first person they interview after the 4th commercial break (around the 45-50 minute mark with commercials/also the last person they mention before the 4th break) is almost always a red herring.

When a cold momma gets hot, boy how she sizzles!

I noticed early in the show's run that if a character is caught lying about one thing early on, they're likely lying about being the killer too.

This is obvious and often applies to other procedural shows as well, but if a big name guest star isn't the killer or sometimes the victim, there's a good chance that they are the doer. It doesn't always apply, but often enough that it's a recognized trope.

Edit: I'm not quite sure what I meant here, but I think I meant if they weren't the victim or sometimes the false lead killer that the chances were they'd turn out to be the killer. Like Bruce Boxleitner in Goodbye Room - it looked for a while like he might be the killer because of being the baby's father, he was also the best known name of the episode, so I thought for a while that he'd turn out to be the killer.

Point 2 is very true for the CSI's: when they introduce some lawyer, probation agent etc..he's likely to be the killer..

The last person you would expect is also a good hint.

All typos and misspellings courtesy of a public educational system.

They give away the killer in EVERY episode. I've literally guessed the killer in everyone, but something still makes me watch more episodes? Lol. Basically I've seen it goes like this with most mystery murders, but more-so with CC.

1: There are so many red herrings. Usually the giveaway is if in the opening scene a character is seen often, but isn't the victim. For example, in the pinultimate episode the teacher whom was seen around prom was noticable, he was the murderer. Not the victim.

2: They never have a better off life because of it. Never fall into that trap! If they do, it's a rarity. But on CC? Never. At least no examples that I can think of.

3: When it reaches around the 30 min mark, they will have a penultimate flashback. In that flashback, either a place is mentioned where the victim is headed (usually the place of work of a suspect/where they were last seen) or you will actually see the murderer in the background! They're usually a lurker. There's never ever a logical story to any of them.

4: When a big star is not playing a role of their caliber is an obvious one. I kinda wish I didn't storm through Cold Case now, I want to watch more :(