Problems
False positives and contamination by subsequent handling or nearby objects (e.g. mixing of blood from victim and attacker), for example, are problems owing to the presence of many common substances and the necessity of human involvement in the collection of trace evidence. Both can occur with DNA traces and fingerprints. Partial fingerprints are even more vulnerable to false positives. Samples from accidents or crimes should therefore be protected as much as possible by enclosure in a sealable container as soon as possible, after an incident is under investigation.
Read more about this topic: Trace Evidence
Famous quotes containing the word problems:
“More than a decade after our fellow citizens began bedding down on the sidewalks, their problems continue to seem so intractable that we have begun to do psychologically what government has been incapable of doing programmatically. We bring the numbers down—not by solving the problem, but by deciding it’s their own damn fault.”
—Anna Quindlen (b. 1952)
“Hats have never at all been one of the vexing problems of my life, but, indifferent as I am, these render me speechless. I should think a well-taught and tasteful American milliner would go mad in England, and eventually hang herself with bolts of green and scarlet ribbon—the favorite colour combination in Liverpool.”
—Willa Cather (1876–1947)
“I believe that if we are to survive as a planet, we must teach this next generation to handle their own conflicts assertively and nonviolently. If in their early years our children learn to listen to all sides of the story, use their heads and then their mouths, and come up with a plan and share, then, when they become our leaders, and some of them will, they will have the tools to handle global problems and conflict.”
—Barbara Coloroso (20th century)