William Ardoin, mug shot courtesy Aurora police.

AURORA | A day before police found Erik Leon Baker’s body in a northeast Aurora ditch in early January, Baker’s friend called police and told them he watched the 44-year-old man get killed.

Baker had walked up to a drug dealer’s house near East Sixth Avenue and Kenton Street, the friend said, and the moment the door opened, someone shot Baker in the head and dragged his body to a nearby car.

But that eyewitness account doesn’t appear to have been enough for police to file charges in Baker’s slaying.

Instead, over the next six months, Aurora police homicide detectives launched a massive investigation into the case, interviewing dozens of witnesses in Colorado, some in Louisiana and traveling to Southern California to interview others. Police also combed through a mountain of cell phone records, including text messages and cell tower data showing where the suspected killer’s phone had been used in Texas, Colorado and Louisiana after the slaying.

This week, police announced charges against three people they say were involved in Baker’s killing or in helping to cover up the crime.

William Ardoin, 34, is facing a first-degree murder charge, as well as lesser charges, police said.

Barbara Walker, 29, and  Raymond Walker Sr., 64, have been charged with accessory to murder.

According to Arapahoe County jail records, Raymond Walker is being held on $50,000 bail and is due in court June 18 while Barbara Walker due in court next month and is also being held on $50,000 bail.

Ardoin is being held without bail.

Court documents in Ardoin’s case have been sealed, but in lengthy arrest affidavits filed against the Walkers, police detailed a lengthy investigation that led to the arrests.

According to the affidavit, Ardoin was Walker’s boyfriend and Walker Sr. is her father.

Early on New Year’s Day, a witness told police he drove Baker to the house Barbara Walker and Ardoin lived in at 890 Kenton St. The man told police he wasn’t sure why Baker wanted to go there, but other witnesses said Baker was angry with Ardoin because Ardoin didn’t pay him what he promised for a pistol a day prior. Other witnesses said Baker may have believed Ardoin, who went by the nickname “Chill Will” and “Cola,” was sleeping with Baker’s girlfriend.

Police said the witness told them a man matching Ardoin’s description shot Baker. Other witnesses told police Ardoin believed Baker was trying to attack him but other said Ardoin shot him for no reason.

After the slaying witnesses told police Ardoin and Barbara Walker went on the run, but not before Walker Sr. helped them by watching Walker’s toddler son.

Investigators said Walker Sr. also lied to them in the weeks after about his daughter’s whereabouts and when he had contact with her.