Thank you for your question.
The private investigator can testify in your daughter's case as a witness at a hearing where his testimony may be relevant. The report can also be admitted as evidence as a business memorandum, which is an exception to the general rule prohibiting the introduction of evidence which constitutes hearsay. The report would have to be properly certified by the private investigator, and failure to do so would mean that the court would not accept it as evidence.
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