Evidence Handling, Chain of Custody, and Report Writing
Courts judge investigative work by whether it can be authenticated and explained. This domain tests chain-of-custody documentation, digital evidence handling, and report writing that separates observation from inference.
Chain of custody
- Log every transfer - who, what, when, where, seal number - on a signed form. Use tamper-evident packaging, unique item numbers, and a photograph of each item at collection.
- Store items in a locked, access-controlled space. A documented gap goes to weight, but a serious gap invites exclusion or destroys credibility.
- Authentication under La. C.E. art. 901 requires evidence sufficient for a finding that the item is what it is claimed to be; the chain supports that finding.
- Digital evidence: never work from the only copy. Image or copy with a hash (SHA-256), record the tool and version, preserve metadata, and capture full URLs, account identifiers, timestamps, and screen video for social media.
Report writing
- Write facts, not conclusions. Staggered gait, slurred speech, and odor of alcohol beat appeared intoxicated; entered at 14:07 and remained until 22:41 beats stayed all night.
- Identify the source for every assertion: personally observed, document reviewed, or person interviewed. Attach an evidence index.
- Never rewrite a delivered report. Issue a dated supplement.
Worked example
A witness shows you a threatening text thread. Photograph the screen with the phone and its number visible, record make, model, and IMEI, export the thread with a forensic tool, hash the export, and log each step. The report states the method, not just the content, so the opposing side cannot argue the messages were fabricated.
Traps
- Conclusion-of-law phrasing such as she committed adultery.
- Destroying original notes after typing the report.
- Failing to record time zone, camera clock settings, or the absence of expected evidence.