Brown denounced the two doctors involved for having "violated their ethical obligations as physicians," and said the patient, in this case Anna Nicole, is not to blame, even if she had a hand in obtaining the drugs.
"These three individuals repeatedly and excessively furnished thousands of prescription pills to Anna Nicole Smith, often for no legitimate medical purpose," he said.
"Doctors are licensed to avoid those pressures."
As for a possible motivation for the accused, Brown said Smith herself may have been a draw.
"Probing into motives is always a speculative undertaking, but certainly there is a...gain here to be part of the celebrity glitz and glamour.
"These people were caught up with being in a relationship with and being around Anna Nicole Smith."
Meanwhile, Kapoor's medical mentor, Dr. Victor Kovner, who started the Studio City medical center currently run by Kapoor, told E! News he was "very saddened" by the situation and insisted Kapoor was "very well trained."
Kovner added that while he wishes the best for Kapoor, it would indeed be a serious crime if the allegations proved true, particularly the charge that he prescribed medications to false names.
"If they did it under another name to deliberately deceive, that's certainly a felony," he said. "His career is in tremendous jeopardy."
Another blast from the past, Smith's estranged mother Virgie Arthur, also wasted no time in commenting on the legal action.
"She was glad to learn of the developments and she expected to sleep well last night," Arthur's attorney, Neil McCabe, told E! News. "As always, she wants justice for the death of her daughter and her grandson."
In addition to the conspiracy charge, the trio variously faces charges of obtaining an opiate prescription by fraud, deceit or misrepresentation; obtaining an opiate prescription by giving a false name or address; prescribing, administering or dispensing a controlled substance to an addict; and unlawfully prescribing a controlled substance.
Brown said that just one count typically carries a three-year sentence.
"This is serious stuff," he said. "Our goal is to prepare the evidence as well as possible. Now it's up to the district attorney and his discretion to handle it the best way possible."
Stern and Kapoor turned themselves in last night and were released on $20,000 bail after getting booked on the charges. Eroshevich has yet to surrender to authorities, but is expected to do so by Monday.
All three are scheduled for arraignment on May 13.
—Additional reporting by Whitney English
(Originally published March 13, 2009 at 10:37 a.m. PT.)