Kasem's children claimed at a Friday news conference that the investigation into Jean Kasem's care that began last June has stalled.
But police spokeswoman Jane Kim says detectives are still actively investigating, though she wouldn't provide details.
The district attorney's office says no case has been presented to prosecutors.
Kasem's wife of more than 30 years and his children from a previous marriage fought over the radio personality's care in his final days.
Daughter Kerri was appointed caretaker and has said her stepmother's actions shortened Kasem's life.
Jean Kasem has denied she caused her husband harm. Her lawyers did not respond to calls seeking comment Friday.