Investigators seek answers to Houston's death

[Confusious]

7. It's not CSI

each thing has to be checked for individually. There's a test for cocaine, heroin, etc . Each of the tests is probably based on a reaction, and each one takes time. They don't happen automatically, and all at once.

If you have the big ones come back negative, then you have to start looking for other things, which takes more time.