Although the use of polygraph results as evidence in court is regularly challenged - it IS a useful tool and is used in the preliminary stage of many criminal investigations.
no
Not in the US
your dog
Most states do not accept psychophysiological veracity (PV) examination (polygraph) results in a civil court cases
Yes, if it doesn't violate the rules of evidence.
A judge has final say on what is or is not admissable in their court. The only recourse if the evidence was refused is to file for an appeal and have the appeals court see if his/her refusal of the evidence was justified. If they find in favor of the judge, you're out of luck. If on the other hand the appeals court decides the evidence should be admissable, the case will most likely be retried with the new evidence presented.
No.
It will depend on the evidence, but probably yes. In most cases the report is not the entire recollection of the police officer.
Yes, it MAY be allowed. The "age of reason" for children in most states is usually set at, or about, 7 years of age.
Yes, if the evidence has already been ruled admissable in court, it can be used again. The more evidence that proves the point, the better.
If it used to quote a necessary piece of overheard dialogue, or to quote what a defendant or other principal in the case said, yes. To simply testify and/or use it in everyday court conversation and answers to other questions, no, it is not.
The legality of using lie detectors, or polygraphs, varies by country. In the United States, their use is common in specific contexts, such as employment screening and criminal investigations, but results are not typically admissible in court. In the United Kingdom, polygraphs can be used in certain circumstances, such as for monitoring sex offenders, but are not widely accepted in legal settings. Other countries, like Canada and Australia, have more restricted or limited use of polygraphs, primarily for investigative purposes rather than as definitive evidence.