The Bone Bed by Patricia Cornwell

The Bone Bed (A Scarpetta Novel) - Kay Scarpetta receives an emailed video clip the night before she is to testify in court about an email she sent to the prosecuting attorney.  The next morning she is called to a scene where a leatherback turtle is entwined with fishing line, and the body of a woman in the bay.  While she is retrieving the body from the water, she is filmed by a helicopter that belongs to the defendant.  Although the woman has nothing to do with the trial, the judge allows the clip to be shown, and it is supposed that the woman that the man on trial is accused of murdering.  Meanwhile, the FBI, is accusing Pete Marino because he had tweeted the woman months before she was discovered.