a portion of the heroin, Parker told
Williams it was of poor quality and to return it to Adams's son, which Williams did.
The government's expert testified that in the June 14, 2001, conversation Parker had
acted as the middleman in brokering a heroin deal between Adams and Rush. The
expert also testified that 40 ounces was a distributable amount of heroin.

       In addition to introducing evidence as to the charged conspiracy, the
government introduced evidence relating to a heroin distribution conspiracy
involving brothers Edward and Joseph Serrano ("Serrano conspiracy").2 Randall
Jackson, who pled guilty to being a member of the Serrano conspiracy, testified that
from 1997 to 1999 Adams had purchased heroin from the Serrano brothers, who lived
in Los Angeles, California. Jackson also testified that he and several womenhad
made multiple round-trips for Adams between St. Louis and Los Angles to purchase
heroin from the Serrano brothers and bring it back to St. Louis for resale. According
to Jackson, Adams lost the Serrano brothers as a source of heroin in September 1999



      2
       The Serrano investigation resulted in a thirteen-defendant indictment in the
United States District Court for the Eastern District of Missouri. United States v.
Aguilar-Sanchez, No. 4:01-CR-00450 (E.D. Mo. Oct. 25, 2001). Except for two
fugitives, the defendants pled guilty.

                                       