Crime Fiction and the Chain of Custody

crime writing

Photo Credit: Julie Elliott-Abshire


When writing crime fiction, it’s important to make sure your characters don’t do anything that would compromise the evidence and cause it to be inadmissible in court.
One way this can happen is if the chain of custody is broken.

What is Chain of Custody?

Chain of custody, according to FindLaw, is defined as “. . . the documentation and proper care of evidence, from its seizure by police to its presentation at trial. If the chain of custody is broken, the evidence may lack credibility and could be deemed inadmissible.”

Why is this Important?

Every case that goes to trial is controlled by the evidence that is introduced. This is the only criteria that a judge in a bench trial or a jury in a jury trial are to use to determine the guilt or innocence of the defendant. They are not allowed, by law, to use any other means to come to a conclusion.

The evidence your characters collect and handle throughout your novel have a large bearing on the outcome of your book, especially if there will be a trial.

You also want to think about the credibility of yourself as a writer and your novel. Readers are more sophisticated these days with criminal investigation and will call you out on it.

How is Chain of Custody Established?

The chain of custody starts with the officer that finds it. Here is a list of a personnel that could be part of the chain of custody:

  •  The officer / investigator who recovers the evidence. This could be a uniformed officer, Deputy/Coroner, Medical Examiner, Crime Scene Investigators, Detective in charge of the scene, or someone else;
  •  The person who takes charge of the evidence at the scene. Again, it could be someone listed in Number 1, or an evidence technician designated to take charge of the evidence at the scene
  •  The person who transports the evidence to the Laboratory. Ideally, it should be someone from Number 1 or 2 above;
  •  The person who receives the evidence at the Laboratory. In my story, it went to the Laboratory Director;
  •  The Laboratory scientist who will examine the evidence;
  •  Whomever retrieves the evidence from the Laboratory after it has been processed.

Chain of Custody Form

Chain of custody labels are good for the permanent marking of evidence. They are printed on tamperproof stock and stick to almost anything. They can be used for marking individual articles, packages and containers.

This form must be attached to each evidence container. It is the job of your characters to properly document who found the evidence, who has it and where it is. If this isn’t done properly, your evidence may not be admitted at trial.

Since any person who handles the evidence has to be able to show an unbroken chain of custody, it’s a good rule of thumb to minimize the number of people who come into contact with the evidence. The shorter the chain the better.

Who is Responsible for the Chain of Custody of Evidence?

The Prosecution must account for the evidence from the discovery, collection, analysis, storage, and transfer to the courtroom. Throughout the entire process, including court proceedings and appeals, the prosecutor is responsible for securing the evidence.

If the defense cannot get the evidence excluded pretrial, they will look to discredit how it was handled during the investigation.

Example from my book, Cause of Death

In my book, Cause of Death, I had a sub-plot that involved a piece of evidence. It was a knife with the fingerprints of the defendant who was on trial for a robbery. It was the only piece of physical evidence the prosecution had. Unfortunately, when it was time to introduce the knife into evidence, it couldn’t be located. Even though it was eventually found, the fact that it was missing even for a short time caused the chain of custody to be broken. The evidence wasn’t admissible and the defendant walked adding to the plot.


Ensuring that your characters don’t accidentally cause a break in the chain of custody of evidence will protect them from charges of tampering, planting, theft, substitution of evidence, and contamination of evidence.

Any time you have a character who has anything to do with evidence at a crime scene, or after, make sure they take the necessary precautions to honor the chain of custody.

(I originally wrote this blog as a guest post on, the blog of Joe Giacalone in July 2013.)