Bloodstain pattern analysis presents a dilemma for forensic science: it is based on math and physics and would seem to have a solid foundation but the interpretation of the patterns can be difficult and subjective. It was an area that was hammered by the 2009 NAS Report (see Supplemental Material, page 177-179 of the manual, or 199-201 of the pdf, and by extension areas of the recommendations offered).
How do you reconcile this contrast that BPA is fudamentally based in math and physics, and science, but is subject to interpretation and heavy subjective review? Do scanners at crime scenes help resolve this? Why or why not? Discuss areas of BPA where there are open areas for interpretation and why, and areas that have subsequently, since 2009, been covered in research (i.e., a lot has changed in 5 years but this publication is still heavily relied upon). You might start out your discussion by describing what BPA is (as a hint).