After a two-day break, Conrad Murray's involuntary manslaughter trial resumed Wednesday.

The prosecution called its final witness to the stand again: Dr. Steven Shafer (above, right), who was hired 20 years ago by the company that produces Propofol -- the drug that killed Michael Jackson -- to calibrate the correct dosage for the drugs. A recap:

  • He said keeping records of patient care is critical. Murray did not. Shafer called this "unbelievable."

  • He said the 15.5 liters of Propofol Murray bought for MJ's tour -- about four gallons worth -- was "an extraordinary amount" to use on one person.

  • Shafer said Murray's lack of basic monitoring devices was a violation of care.

  • Shafer described Murray's treatment of MJ as an "egregious" and "unconscionable" violation of care.

  • Shafer said dosage of Propofol is crucial, and that it should only be done through a pump to avoid overdosing (Murray did not.)

  • He said Murray "left the steering wheel" when he went to bathroom to relieve his bladder, leaving MJ alone and under the sedation of Propofol.

The defense will now have its chance to call its own witnesses to the stand.