Which of the following is NOT a technique for obtaining measurements for the crime scene sketch?

• A. Fixed points
• B. Triangulation
• C. Base line
• D. Polar coordinates

Answer: (A)

Understanding how measurements are taken for a crime scene sketch relies on methods that convert space into coordinates using reference points. The main techniques used are triangulation, which uses two fixed reference points to form triangles and locate objects; the baseline method, which fixes a baseline between two points and then measures perpendiculars from that line to determine positions; and polar coordinates, which record distance and angle from a single fixed point to each object.

Fixed points themselves are reference locations, not a complete measurement method. They serve as the anchors or references that the actual techniques use to derive measurements. Without applying a method to those points—whether forming triangles, establishing a baseline, or measuring angles and distances—you don’t obtain the numerical data needed for an accurate sketch. So fixed points aren’t a technique for obtaining measurements on their own, whereas triangulation, the baseline method, and polar coordinates are established techniques that use those references to capture precise scene measurements.