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AGR-CSI53-11 · Lesson 2 · 25 clock hours · practice

Targeted Domain Review: CCSI and Evidence Tech Content

Objective. Working through every CCSI and State Evidence Tech exam domain in weighted order, the learner will answer domain-specific practice question sets and correctly explain the reasoning behind each answer at a rate of 75 percent or higher before moving to the next domain.

⚠ Pending professional review

This lesson, its worked examples and its practice questions has not yet been verified by a licensed professional in the field or by a certification or approval body. It is a study draft and may contain errors. Do not use it as instructions for work on a job site or on live equipment. Always follow your instructor, your supervising professional, and current official references and regulations.

VoTechWorks program approval and accreditation are still in progress. Credentials are issued only by the certifying bodies named in each program, after their own exams.

Why Domain-Weighted Review Matters

Certification exams for the IAI Certified Crime Scene Investigator (CCSI) and State Evidence Tech credentials are organized around tested domains — broad content categories that reflect the real tasks of the job. Each domain carries a different weight on the exam, meaning some areas contribute more questions to your final score than others. Working through domains in weighted order lets you invest study time where it pays off most, then shore up weaker areas before test day.

Today's lesson covers all six major domains that appear across the CCSI and State Evidence Tech exams. Your goal is to answer practice questions at 75 percent or higher in every domain. Below is a concise review of what each domain tests and the principles that drive correct answers.

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Domain 1: Scene Documentation and Photography

Documentation creates the permanent legal record of a scene. Photography follows a general-to-specific sequence: overall (establishing) shots, mid-range (relationship) shots, and close-up (detail) shots with and without a scale. Every photograph must be logged in a photo documentation form that records frame number, direction, subject, lighting conditions, and equipment used.

Sketch and measurement duties accompany photography. A rough sketch is drawn at the scene with measurements; a finished sketch is produced later to scale. Triangulation, rectangular coordinates, and baseline methods are standard measurement techniques. Accurately placed measurements allow scene reconstruction later and support courtroom presentation.

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Domain 2: Evidence Collection and Packaging

Evidence integrity depends on choosing the correct collection tool (swab, forceps, cutting, casting) and the correct packaging material for the evidence type. The general rule: biological evidence (blood, saliva, tissue) must be packaged in paper to allow moisture to escape and prevent mold and DNA degradation. Dry, non-biological trace evidence may be packaged in paper or plastic, depending on its characteristics. Sharp objects require rigid, puncture-resistant containers.

Safety first: Before collecting any unknown substance, assess the hazard. Wear appropriate PPE — at minimum nitrile gloves and eye protection; add respiratory protection if airborne particles, unknown powders, or chemical hazards are suspected. Never reach into a container or bag without inspecting it visually first. If a clandestine lab or hazardous material is identified, withdraw from the scene and notify the appropriate HazMat authority before proceeding.

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Domain 3: Chain of Custody and Legal Standards

Chain of custody (COC) is the documented, unbroken record of who collected, handled, transferred, or analyzed a piece of evidence. Every link in the chain must be documented with the person's name, date, time, and purpose. A gap or undocumented transfer gives the defense grounds to challenge admissibility.

Key legal standards: evidence must be relevant, material, and competent to be admissible. The Fourth Amendment governs search and seizure; always clarify whether a warrant, a recognized exception (plain view, consent, exigent circumstances), or a court order authorizes collection before touching evidence. State Evidence Tech requirements may add jurisdiction-specific documentation or handling rules.

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Domain 4: Crime Scene Reconstruction Basics

Reconstruction uses physical evidence, documentation, and scientific analysis to determine the sequence and manner of events at a scene. Bloodstain pattern analysis, trajectory analysis, and the positioning of evidence items all contribute to reconstruction. The investigator identifies point of origin, directionality, and sequence of events from patterns rather than assumptions.

Reconstruction is hypothesis-driven: form a hypothesis from evidence, test it against all physical data, and revise it if contradicted. Avoid confirmation bias — the tendency to stop collecting data once a preferred theory is supported. Every conclusion must be supported by documented, reproducible observation.

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Domain 5: Courtroom Testimony and Report Writing

Reports must be factual, objective, complete, and written in plain language. They record observations, not conclusions beyond the technician's expertise. Use active voice, past tense, and standard abbreviations only. Avoid opinions on guilt or ultimate legal conclusions unless you are qualified as an expert witness in that specific area.

On the stand, a crime scene technician typically testifies as a fact witness about what was observed and collected. Expert witness status requires additional qualification by the court. When cross-examined, answer only the question asked, acknowledge uncertainty honestly, and never argue with opposing counsel. Your report is your foundation — inconsistencies between your testimony and your written report damage credibility.

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Domain 6: Safety and Scene Management

Scene safety is the first priority — always. Upon arrival, assess for active threats, structural hazards, electrical dangers, biohazards, and chemical hazards before entering. Establish and maintain a perimeter appropriate to the scene type. Control access using a scene entry log; record every person who enters or exits.

PPE selection must match the hazard level. Standard crime scene work requires, at minimum, gloves and eye protection. Bloodborne pathogen exposure requires gloves, face shield or mask, and protective clothing per OSHA Bloodborne Pathogens Standard guidance. Unknown chemicals require stopping and contacting HazMat. Remove and properly dispose of contaminated PPE before leaving the scene perimeter to prevent cross-contamination of other areas.

Key terms8

Chain of custody (COC)The documented, unbroken record of every person who collected, transferred, handled, or analyzed a piece of evidence, from collection through courtroom presentation.
Domain weightingThe proportion of exam questions assigned to each content area; higher-weighted domains contribute more to the final score and deserve proportionally more study time.
General-to-specific sequenceThe standard crime scene photography progression from overall/establishing shots, to mid-range/relationship shots, to close-up/detail shots with and without a scale marker.
Confirmation biasThe cognitive error of stopping data collection once a favored theory appears supported, potentially ignoring contradictory evidence; must be actively avoided during reconstruction.
Fact witnessA witness who testifies only about personal observations and actions; a crime scene technician's default testimony role, distinct from an expert witness who may offer opinions.
Biological evidence packaging ruleThe principle that biological evidence (blood, saliva, tissue) must be packaged in paper rather than airtight plastic to allow moisture to escape and prevent DNA-degrading mold growth.
Scene entry logA written record maintained at the scene perimeter documenting the name, agency, purpose, and entry/exit times of every person who enters the crime scene.
Reconstruction hypothesisA testable, evidence-based explanation of the sequence and manner of events at a scene, which must be revised whenever physical evidence contradicts it.
In class: Rotating station review: six stations are set up around the classroom, each covering one major CCSI/Evidence Tech domain (scene documentation and photography; evidence collection and packaging; chain of custody and legal standards; crime scene reconstruction basics; courtroom testimony and report writing; safety and scene management). Learners spend approximately 35 minutes per station answering 15 timed practice questions, then review answers as a group with the instructor identifying the standard or principle behind each correct response. · Case-file reconstruction drill: learners receive a sanitized, simplified case packet from a hypothetical scene and must identify which collection method, packaging material, documentation form, and chain-of-custody action applies at each of ten decision points, citing the relevant CCSI domain and state evidence tech requirement for each choice. · Peer-teach remediation: learners whose diagnostic score for a given domain was below 70 percent teach a five-minute mini-review of that topic to a small group using their notes, program textbooks, and IAI reference materials, while the instructor listens and corrects factual errors in real time.
Materials: Domain-specific practice question bank (CCSI and Evidence Tech), case-file reconstruction packets, evidence packaging samples (paper bags, manila envelopes, heat-seal pouches, evidence tape, tamper-evident seals), chain-of-custody form set, program Courses 2–3 and 7 textbooks and handouts, IAI CCSI Candidate Handbook, dry-erase boards for group work
Check: Score on each domain-specific practice set recorded and reviewed; any domain below 75 percent triggers a second practice set completed before end of lesson. Pass mark: 75 percent or higher on each of the six domain station sets, with instructor sign-off on the case-file reconstruction drill showing correct citation of domain and standard at eight of ten decision points.

Practice check8

Answer each question, then check it. Nothing is recorded; this is your own practice.

Evidence Collection and Packaging (CCSI / State Evidence Tech)
1. A technician collects a bloodstained piece of clothing at an outdoor homicide scene. Which packaging choice is correct?
Scene Documentation and Photography (CCSI)
2. During the photography of a scene, the investigator takes overall shots of the room, then moves closer to capture a bloodstain in relation to the furniture, and finally photographs the stain alone with a scale marker. This sequence is best described as:
Chain of Custody and Legal Standards (CCSI / State Evidence Tech)
3. An evidence technician discovers that a property receipt transferring a knife from the collection officer to the laboratory has no transfer date or receiving technician signature. The most significant consequence is:
Courtroom Testimony and Report Writing (CCSI / State Evidence Tech)
4. A crime scene technician is cross-examined and realizes the answer she is about to give contradicts a detail in her written report. The best action is to:
Safety and Scene Management (CCSI / State Evidence Tech)
5. Upon arriving at what dispatch described as a simple burglary scene, the first responder notices an unfamiliar chemical odor and sees several large containers with unlabeled tubing in the garage. The correct immediate action is to:
Crime Scene Reconstruction Basics (CCSI)
6. During a crime scene reconstruction, an investigator's initial hypothesis is that the victim was shot from a doorway. Subsequent bloodstain pattern analysis indicates the point of origin is inconsistent with that position. The investigator should:
Scene Documentation and Photography (CCSI)
7. Which measurement method places both fixed measurement points on the same baseline wall and measures the distance of an evidence item from each point along that wall?
Chain of Custody and Legal Standards (State Evidence Tech)
8. A State Evidence Tech candidate needs to confirm which Fourth Amendment exception allows collection of evidence that is in plain view of an officer lawfully present at a location, without obtaining an additional warrant. That exception is called:
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