In Day Four of one of Brazos County's most high-profile capital murder trials, prosecutors continued building their case against Bryan resident Willie Davis.
Expert witness Lt. Dan Jones with the College Station Police Department took the stand Friday morning.
Jones has served 22 years in law enforcement, and was involved in a multi-county narcotics task force for several years.
Prosecutors asked Jones to describe how drug transactions take place.
Jones testified cash is usually used in exchange for narcotics, and it is possible to be ripped off during a transaction.
Prosecutors used the testimony to tie in their contention local rap producer Tommy Andrade was killed over a drug deal gone bad.
Jones also deciphered ledgers and written documents found in Chad and Willie Davis' possession.
Jones testified the ledgers were full of what appeared to be a log of drug transactions.
Using personal knowledge, Jones testified it looked like the Davis' used code names such as "cds" and "tapes" to signify kilos of cocaine and pounds of marijuana sold.
When prosecutors asked Jones if it appeared the Davis' were involved in drugs, he said "it appears to be a major drug trafficking operation."
Also taking the witness stand Friday was a former employee of Willie Davis' son, Chad. With the help of a Spanish translator, Javier Pacero testified he had worked for Chad Davis for three years washing and painting his house.
Pacero testified in September 2003, Chad has asked him to come with him to Houston to pick up a car. Pacero said he drove a cadillac back for Chad, who then asked him to sell it for $800.
Pacero later testified when he cleaned the car, he noticed several stains in the backseat. Police later picked up the car that was allegedly used during the 2003 murder of Andrade.
More than three hours were spent Friday questioning Texas Ranger Frank Malinak, who served as one of the lead investigators.
Malinak deciphered cell phone records that linked Willie Davis to the hitmen hired by the Davis clan to get revenge on Andrade.
Testimony continues Monday at 9 a.m. in the 85th District courtroom.