Defence lawyers for the doctor charged over Michael Jackson's death are seeking urgent testing of two syringes and an IV bag found in the singer's mansion.
Arguing that evidence was deteriorating, lawyers for Dr Conrad Murray said during a 40-minute closed session with a judge that liquids in one of the syringes had already dried up and was now "salt", according to a transcript of the proceeding.
Quantities of substances in the syringes and IV bag could be crucial to explaining how the singer died, the lawyers told the hearing.
Murray has pleaded not guilty to involuntary manslaughter. Authorities say he administered a lethal dose of sedatives, including the anaesthetic propofol, to Jackson, 50, in the bedroom of his rented mansion in June 2009.
Officials tested what was in the items and found traces of propofol and lidocaine, according to the transcript. But the amounts of the substances were not determined and defence lawyers say that may be significant in the case expected to hinge on technical and scientific data.
Superior Court judge Michael Pastor declined to order testing on the substances on Tuesday because he wanted defence lawyers to confer further with prosecutors.
The judge might order the testing late next week if the two sides can agree on how it will be conducted.
"I want to act as quickly as we can," Judge Pastor told the lawyers.
But defence lawyer Ed Chernoff struck an urgent tone, telling the judge: "We are doing it because the house is on fire. We need a hose."
Prosecutor David Walgren questioned why defence lawyers had not raised the issue sooner. "There are very technical, complex issues," he told the judge, adding he thought an agreement on the testing could eventually be reached.