NCJ Number
47540
Date Published
1977
Length
16 pages
Annotation
FORENSIC LABORATORY ANALYSES OF WOOD SAMPLES CONDUCTED AS PART OF A LABORATORY PROFICIENCY TESTING PROJECT ARE DOCUMENTED IN CHARTS AND TABLES.
Abstract
THREE WOOD SAMPLES REPRESENTING EVIDENCE FROM A CRIMINAL CASE WERE SENT TO 238 LABORATORIES (64 RESPONSES). THE LABORATORIES WERE ASKED TO DETERMINE WHETHER ANY OF THE SAMPLES COULD HAVE COME FROM THE SAME SOURCE, TO INDICATE THE SPECIES OF EACH SAMPLE, AND TO DESCRIBE METHODS OF ANALYSIS. EACH SAMPLE WAS FROM A DIFFERENT SPECIES; SAMPLE A WAS FIR, B WAS MAPLE, AND C WAS PINE. OF THE RESPONDING LABORATORIES, 50 (78.1 PERCENT) DETERMINED THAT EACH SAMPLE WAS A DIFFERENT WOOD. SAMPLE A WAS IDENTIFIED AS FIR BY 16 LABORATORIES, SOFTWOOD BY 7; SAMPLE B WAS IDENTIFIED AS MAPLE BY 20 LABORATORIES, AS HARDWOOD BY 8; AND SAMPLE C WAS IDENTIFIED AS PINE BY 23 LABORATORIES AND AS SOFTWOOD BY 7. OTHER LABORATORIES EITHER DID NOT MAKE A SPECIES IDENTIFICATION OR IDENTIFIED ANOTHER SPECIES. MOST OF THE LABORATORIES USED A COMPOUND MICROSCOPE AND/OR A SIMPLE MAGNIFIER TO IDENTIFY THE SAMPLES. DETAILS OF METHODS AND FINDINGS -- INCLUDING BREAKDOWNS OF RESPONSES FROM INDIVIDUAL LABORATORIES -- ARE PRESENTED IN TABLES. THE SAMPLE SUPPLIER'S CHARACTERIZATION OF THE SAMPLES, AN EXPLANATION OF SURVEY METHODS, AND A COPY OF THE QUESTIONNAIRE ARE INCLUDED. OTHER PROFICIENCY TESTS ARE REPORTED IN NCJ 47522-47539, 47541-AND 47542. (LKM)