Dr. Conrad Murray has officially been charged with involuntary manslaughter in the death of legendary pop singer Michael Jackson. It took this long to bring Murray to justice because the DA’s office doesn’t have much of a case against him.

The DA’s office will have to prove that Murray — even involuntarily — caused the death of Jackson by plying him with the sedative/anesthetic Propofol and other prescription drugs. But the coroner’s report doesn’t support that charge since Jackson frequently self-medicated with a personal pharmacy stash of drugs. Any of those drugs in his body in any combination could have killed him.

According to the criminal complaint, the D.A. alleges Dr. Murray “did unlawfully, and without malice, kill Michael Joseph Jackson … in the commission of an unlawful act, not a felony; and in the commission of a lawful act which might have produced death, in an unlawful manner, and without due caution and circumspection.”

Dr. Murray will be arraigned today at 1:30 PM. As we first reported, he will plead not guilty.

Dr. Murray is expected to show up at around 1:00 PM, accompanied by his lawyers and a bail bondsman. Bail should be set at $25,000.

Dr. Murray administered Propofol to Jackson just before he died, and the L.A. County Coroner’s Office has determined Jackson died as a result of acute Propofol intoxication.

If convicted, Dr. Murray faces a maximum of four years in prison.