Circumstantial evidence is evidence in a case which can be used to draw inferences about a series of events. It is also known as indirect evidence; the opposite is direct evidence. This type of evidence is an important part of any criminal trial, and both sides in a trial will generally try to find some to support themselves. Contrary to popular belief, it is possible to obtain a conviction with the use of circumstantial evidence, if it is backed up by corroborating evidence and other factual information.
A classic example of circumstantial evidence would be testimony from a witness who arrived at a crime scene to find someone holding a smoking gun. The person holding the gun could have committed the crime in question, but he or she could also be an innocent bystander. A piece of corroborating evidence to support a case against the person holding the gun might come from another witness who testifies to hearing a gunshot seconds before the first witness arrived on the scene, suggesting that the murder would not have had a chance to get away.
Essentially, circumstantial evidence paints a picture of the details of the case. Good lawyers are very talented at extracting evidence in a way which will support an end point. They can also undermine this type of evidence by making the witness seem less credible, using a variety of techniques. The acceptance of circumstantial evidence in a case can make or break the verdict, especially when there is little direct evidence to link the accused with the crime.
If a witness says that he or she saw someone shoot someone else, this is direct evidence, because it requires no inferences. This witness saw the murder or injury and testifies to that effect. In a case like this, circumstantial evidence might be used to support the testimony of that witness, to ensure that the prosecution has a tight case. The defense may also attempt to use evidence to undermine the case of the prosecution by clouding the details of the event in question.
In many courts of law, juries and judges are required to consider all available evidence before making a decision. In a case with a severe punishment, the prosecution must generally prove their case beyond a reasonable doubt. In a case like this, circumstantial evidence must be carefully gathered and corroborated so that the evidence paints a clear and obvious picture. Should the prosecution fail to prove the case, the perpetrator could go free.