Flies and maggots can tell investigators when people died and whether they took drugs. They can also help solve cases involving the living.

M. Lee Goff, a University of Hawaii entomologist who runs a Honolulu company called Forensic Entomology Enterprises, said police usually call him to help figure out how long someone's been dead.But last summer he got a different question: How long had a baby - barely alive and covered with bruises and maggots - been left near a Hawaii lake?

"She was quiet enough that flies had been attracted. Initially, they were attracted to the feces in her diapers," Goff said in New Orleans last week at a conference of the Entomological Society of America.

Based on the maggots' size and other factors, the insect expert estimated the baby had been there 27 hours.

He testified at the trial of the child's mother, Sharon Klafta, 32, who was convicted of attempted murder in September for leaving 16-month-old Heather near the lake in April.