Just my opinion, so take it with a grain of salt, but my understanding is that LE has 2 priorities: find the missing person, and legally obtain evidence leading to a successful prosecution of the perpetrator(s). Part of the rules of engagement include that LE can withhold information, tell false information including lies, and/or mislead parties as investigative methods while searching for the truth. These can NOT be done by the prosecutor in prosecuting the criminal charges. There, the suspect, who is presumed innocent, has the right to the truth and any withholding of information, lies, or misdirection may well lead to charges being set aside, a mistrial, a successful appeal of a conviction, etc. Just my thoughts, fwiw.