So let's be real clear. There are two categories of evidence: direct evidence and circumstantial evidence.
Circumstantial evidence is any evidence other than personal knowledge or observation of the facts in question. It's called circumstantial because it is a circumstance from which guilt can be inferred. If you break down that definition, as we did in evidence class oh so many years ago, you come to realize that direct evidence boils down to pretty much one thing: the testimony of eyewitnesses to the incident, which includes confessions.
Anyone who was there at the scene of the crime has personal knowledge of it. That person observed the incident.
Anything else is circumstantial evidence.
So when we're talking about evidence produced at a criminal trial, let's go through some examples to think about what is direct evidence of guilt and what is circumstantial evidence.
- A co-defendant testifying against the defendant, detailing their actions, should be easy. That's direct evidence.
- A witness testifying she saw the defendant come stumbling out of the building covered in blood and holding a bloody knife 5 minutes before the stabbing victim is found? Unless that witness personally observed the defendant plunging the knife into the victim, it's circumstantial evidence of guilt. It is certainly compelling evidence, but it's circumstantial.
- The defendant's DNA at the scene of the crime or fingerprint on the gun is circumstantial. It doesn't prove that the defendant was at the scene committing the crime (or even at the time of the crime) or pulling the trigger. It's just a circumstance that makes it really easy to infer the defendant's guilt, but you still have to draw an inference to get to guilt.
- Evidence from a red light camera that your car drove through the intersection at a time consistent with leaving the crime scene is circumstantial.
- Evidence that you hated the victim is circumstantial.
- Pretty much any other evidence you can think of is circumstantial.
A lot of people think physical evidence is not circumstantial evidence, which strikes fear into my heart. Because what they're really saying is it is ironclad proof of guilt. So a defendant's fingerprint on the murder weapon doesn't need to be analyzed to determine if it has any probative value because it is direct proof that the defendant pulled the trigger. But that isn't right, not at all. A fingerprint or DNA on the gun is circumstantial evidence. A jury must still consider whether the particular piece of physical evidence proves the defendant's guilt, or whether it just proves the defendant was at some point in time in contact with the gun. I certainly hope they don't skip this step!
Didn't anyone ever see the Harrison Ford movie? Turned out his semen in the victim wasn't because he'd raped and murdered her. It was *spoiler alert* there because his crazy wife saved semen off her diaphragm, froze it, and then placed it in the victim to frame her husband for the murder. This crazy movie perfectly highlights why physical evidence is still just circumstantial evidence.
Some evidence is weak, some more compelling. But whether the evidence is weak or compelling does not depend on whether it is direct or circumstantial evidence. Eyewitness testimony can be incredibly flawed. Conversely, circumstantial evidence (like a defendant's bloody footprints, DNA, and fingerprints all over the crime scene) can be overwhelming.