Inside The First Steps Of Every Investigation | Forensic Files

As a crime scene investigator, you can never go into a crime scene with a theory or an assumption. I've spent two
decades of law enforcement as a crime scene investigator, and I've been sharing my expertise with Ashley Flowers
on Crime Junkie for years. I'm going to walk you through how we approach a crime
scene, just like how we train new investigators. As crime scene investigators, we go through a rigorous
process and use all tools available to answer the questions and solve the crime.
There are several key steps in analyzing a crime scene. Securing a crime scene is all about
making sure that evidence isn't tampered with. You don't want any artifact evidence there from somebody coming into
the crime scene. Meaning, if you have an individual who comes in and leaves their
DNA, that becomes artifact. It's not evidence to that actual crime. After securing the crime scene, it's a waiting
game. It's waiting on getting that search warrant. Once you finally get that search warrant, the very first
thing in that interior barrier is you create a crime scene entry log. Those very first people who go into there are
your forensic services unit members who are going to photograph and document the
crime scene. Documentation is the most important thing. This starts on the exterior. Photographs
are taken of the complete exterior of the house from all sides, all corners of the house. And then you start at the
entryway of coming into the crime scene, and you photograph everything. You photograph every room from wide angles,
from every corner. Especially now in the digital age, hundreds if not thousands of pictures. I've seen cases where
there's upwards of 3,000 pictures. For some of the advanced documentation of crime scenes, you can use 3D
scanners. You can actually do a 3D fly-through through your crime scene. In crime scenes where we feel there's been
crime scene cleanup, we can use Luminol. This is Luminol. Luminol is used to identify blood that's
been cleaned up before. With this product here, you add water to it, you mix it up, and then you spray it on the
area where you think that blood had been or or any kind of biological fluid, seminal fluid, things like that. And
when you put a black light over top of it, it'll show you where that area is. Now, we want to start identifying
evidence. So, here, as we're standing in this room, our biggest piece of evidence here is
our victim. So, we then take markers, and we put markers down. When we write our report, the victim's body is at tent
number one. And then we're going to take photographs of our victim with a mark. Bullet holes are going to get number
two. They're photographed prior to the tent going down, and they're photographed after the tent goes down.
We always put a scale in that photograph next to that piece of evidence for reference. Continuing through, you would
mark the blood, photograph beforehand, photograph afterwards. You put a tent. Same thing with the other blood stains,
and then you work your way out of this room. And here, directly in the hallway, we have bullet casings. Photograph the
bullet casings, and mark the bullet casings with a tent. So, that's documentation.
We then get into the collection process, which is super important how you collect
your evidence and how you package your evidence. So, for example, in this crime scene, if we had a weapon here, we use
weapon boxes. They have knife boxes, they have gun boxes, they have rifle boxes to be sent to the lab for DNA
testing. When we collect other evidence, when we start talking about blood, if it's blood on the floor as we have here,
they swab the blood. And it's really just an extra-long Q-tip, but they're sterile. You let that dry, and then you
package that either in a box, something a little bit bigger than this, or you package that in a paper bag. We utilize
paper bags more than plastic bags now because paper bags don't cause mold, don't cause degradation of your evidence
when you package it. And also, we want to figure out what the trajectory of those bullets were, where they
originated from and where they ended up. To do that, we use lasers to identify that trajectory of the rounds. So, if
you know the point where it ends and you know the point in the middle where it kind of comes through the victim's body,
then you can then create a trajectory where you can go back and create the starting point.
Then also here, we have broken glass in our dining room area. Again, collect it and placed in a paper bag. And this is
also key for us because this is a great spot to fingerprint. This is a basic fingerprint kit that's used at crime
scenes. These kits consist of powder, which is usually graphite, to put on the area where a fingerprint is, the brush
that you use to dispense the graphite, and then lifting material to actually lift the fingerprint off. At crime
scenes, we utilize all different kinds of instruments to collect evidence, scalpels, box cutters to be able to cut
carpet out. We use saws alls to be able to extract bullets from walls. Outdoor crime scenes have their own
challenges. We're fighting with rain, we're fighting with snow, we're fighting with sun. These footprints that we have
here become relevant to the crime. That evidence is critical to be processed first. They're photographed and they're
cast. Same thing with tire tracks. These tire tracks are in a really odd location. Are they connected to the
crime scene itself? We would still photograph them, we would still take a casting of them.
When casting tire impressions, footprints, you use something of this nature. This is a shaking cast
all-inclusive kit that has water already in with the powder. So, what you would do is you'd lay it flat, you'd press on
the water container, and it would break open, and then you need to get this to like a clay-like consistency, and then
you pour this into your foot impression or your tire impression. You give it 30 minutes to dry, and then you just pull
it right up, and you have your impression. We have evidence of disturbed earth here. Did the offender leave and dig
something and bury the murder weapon here? Did they dig and put other evidence here at the scene? So, they
have metal detectors that we've used before. They have ground-penetrating radar, where they actually can run over
that section of earth and identify an anomaly. But, the critical piece of it is is how far down we believe it to be.
We've used excavation equipment before to recover bodies that have been buried, and we can identify the depth of the
body. So, what you'll do is dig down maybe a foot above that body, and then from there down you're digging by hand.
But, any kind of earth that we dig up, we sift everything, and it's sifted for other evidence that may be buried there
also that we can't physically see. So, some of those other things that we deal with outside, especially outside crime
scenes where you have a deceased person, a lot of times they're in a state of decomposition, where they're either A,
maggots have already started to form, or B, you have blowflies flying around the
body. So, what you want to do is you want to collect those insects, cuz you can send them to an entomologist, and
they can give you a rough time of death. With a maggot, you can tell how old they
are and how long they've been there by the size of the maggot. So, that's what an entomologist does. I love maggots.
Maggots are the best. I'm telling you right now. And then after that, there's always a
final walk-through. When we start analyzing crime scenes, we try to start a point of entry. Where's that point of
entry that we think the offender came into the house at? And where is that interaction between both the offender
and our victim? Point of entry we have here into the house, we saw the broken glass. This is that exterior door. So,
when the offender broke into the house, he broke the glass and it fell inside the house. And then you kind of look at
this blood here. Is this our victim's blood or is this our offender's blood that got onto the offender when the
offender comes out of the room? Or is this somehow an altercation between our victim and our offender and our offender
is bleeding himself? So, these blood droplets outside of the main crime scene become super important. Because
obviously as you see here, it does not look like our victim moved after he was shot. Our offender comes into the room,
he surprises the victim, the victim stands up, is more than likely initially shot here where we have our first set of
blood stains, and then falls to final rest, and we have the other blood here at final rest.
So, it kind of gives you an idea of what happened here. But, some of the things that we don't see and are super
important is the motive. Is anything stolen? Is anything missing? Do we think this person came here to steal something
or is this personal? These are those key things you start picking up on at crime
scenes. Taking in all the evidence including statements, what we get at the autopsy,
helps us create a hypothesis of what had happened at that crime scene. Technology is changing all the time and
people are really focused on going back to cases, but dusting them off and looking at the evidence and say, "Hey,
is there something we can do now in 2026 that we weren't able to do 40 years ago.
Maybe there's nothing we can do today. Maybe there's nothing we can do in 5 years, but we need to preserve that. So,
if in 10 years from now, if new technology comes about, in case it's not solved, that we can have that for
future.

What actually happens when investigators arrive at a crime scene? In Crime Junkie special, friend of Ashley Flowers, Patrick “Zip” Zirpoli, a former Pennsylvania State Police Corporal with over 22 years of experience in homicide investigations, cold cases, and missing persons, breaks down the real process, step by step.

Zip isn’t just any expert. He’s led investigations across the state of Pennsylvania, coordinated cold case efforts, worked on child abduction cases, and trained law enforcement agencies across the United States and internationally. Now, he’s walking us through what REALLY happens behind the scenes.

You’ll learn how investigators secure a crime scene and prevent contamination, document every detail using photography, 3D scanning, and forensic tools, identify and collect evidence, from fingerprints to biological material, reconstruct events using trajectory analysis and scene mapping, handle outdoor scenes, including buried evidence and environmental challenges, and preserve evidence so cases can be solved years, or decades, later

Zip also explains why one rule matters above all: Investigators must enter every scene without assumptions. Because once a theory takes hold too early… it can lead the entire case in the wrong direction.

This episode gives you a rare, inside look at real investigative methodology, how evidence is interpreted, and how cases are built from the ground up. -------- Follow Crime Junkie: Instagram: https://www.instagram.com/crimejunkiepodcast Facebook: https://www.facebook.com/CrimeJunkiePodcast/ Twitter: https://twitter.com/CrimeJunkiePod Crime Junkie is created and hosted by Ashley Flowers.

About Ashley Flowers Ashley Flowers is the top female podcaster in the U.S. and the host of Crime Junkie, the #1 podcast among women and the #1 true crime podcast globally. As the Founder of Audiochuck, she has built a top-tier podcast production company that has garnered over 2.6 billion downloads, captivating audiences with its gripping storytelling through 10+ chart topping podcasts. Ashley and her team are dedicated to creating responsible true crime content that respects victims and their families.

Follow Ashley: Instagram: https://www.instagram.com/ASHLEYFLOWERS/ Twitter: https://twitter.com/ash_flowers TikTok: https://www.tiktok.com/@ashleyflowerscrimejunkie Facebook: https://www.facebook.com/ashleyflowers.af/

Check out these other great crime channels: @annieelise Secret Lover, Millionaire Brothers, & A Stalker | Who Took Annie McCarrick? https://www.youtube.com/watch?v=WTe3QlkoyUM @kallmekris The Disturbing Cult Of Scientology https://www.youtube.com/watch?v=NBh3GDoq0Rw @KendallRae Craiglist, Cyberstalking & Catfishing: The Story Of Michelle Hadley https://www.youtube.com/watch?v=YDkIhnTpkCM @bellafiori The Twisted Case of Dan Markel https://www.youtube.com/watch?v=v45cDjLN6ZQ

Brief Summary

Crime scene investigator discusses techniques and evidence collection methods used in investigations.

Key points

The Importance of Documentation. Documentation is crucial in crime scene investigation, starting from the exterior to the interior.
Using Luminol for Evidence. Luminol helps identify cleaned-up blood at crime scenes, revealing hidden evidence.
The Role of Insects in Forensics. Insects can provide crucial information about the time of death in investigations.

Episode highlights

Episode quotes

Documentation is the most important thing.

1:11WatchMay 6, 2026

Tension

45/ 100Some tension

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