Despite the first-hand reports and admissions from the gang members, no one has been arrested for Andrew Graham's murder in Centennial last November.
"This is an on-going and active investigation," said Arapahoe County Sheriff Grayson Robinson, who is leading the murder case. "We will do it right, we will ensure that we conduct our business within the policies and procedures of my office, within the guidance of the criminal justice system. We will do it right, and right often doesn't mean quick. But it will be right."
The 23-year-old graduate student was targeted because the Denver Crips gang wanted to rob a "white" person and Graham "looked like he might have money," according to the affidavits.
Graham was gunned down in the early morning of Nov. 6, 2009 and discovered in the front yard of a home in a neighborhood near the Park Meadows Mall in Centennial. He was going home after looking for a place to live in Boulder where he had just been handpicked by his professors to take part in a new master's program for mathematical engineering at the University of Colorado.
In a polygraph interview with Denver Police on Dec. 9, gang member Clarissa Lockhart said she and four other gang members followed Graham after he got off the light rail and went down a busy street for two blocks.
Lockhart said gang member Allen Ford spoke to Graham. Lockhart says another gang member nicknamed "Baby Low" then shot and killed Graham.
Another gang member, who is a minor, told investigators he was responsible, directly or indirectly, for providing weapons to Baby Low and said Baby Low told him he was the shooter, according to the affidavits.
The alleged killer's full name is in the affidavits, but 9NEWS is only reporting his nickname because he was a juvenile at the time of the crime and has not been charged.
9Wants to Know has learned some of the gang members involved in Graham's murder were part of the racially-motivated violent attacks on white people in Lower Downtown Denver and along the 16th Street Mall last summer, according to the affidavits.
Denver Metro Gang Task Force members say the Crips were targeting white individuals for robberies for about six months before Graham's death. Police say the gang was responsible for robbing, assaulting and attacking as many as 26 people during that time.
That investigation led to the arrest of 31 people, including Crips gang members.
Ford and Lockhart allegedly confessed to taking part in the crimes.
However, 9Wants to Know has learned Denver Police did not arrest Ford in the attacks at that time and reduced the charges against Lockhart.
That meant they were out of jail roaming free months later in November when they headed south with three others and attacked Graham.
According to the affidavit, Baby Low allegedly shot Graham once. The bullet and gun have not been recovered, according to the sheriff's department.
Denver Police arrested Lockhart and Ford later on Nov. 19 in connection with the robberies and assaults. That was 13 days after Graham's murder.
9Wants to Know asked the Denver Police chief, the Denver District Attorney's office and the Arapahoe County District Attorney to comment on the delay in arresting and charging at least two of the gang members in the initial attacks, which may have prevented Graham's murder.
All agencies declined to comment.
"I'm focusing my attention on the investigation that's the responsibility of the Arapahoe County Sheriff's Office," Robinson said. "Because it's an on-going investigation and very active, I have no comment about any other jurisdiction or any other issue."
Robinson is prohibited from talking more about the case because the search warrants have been sealed by a court order.
He was willing to speak about Graham.
"He was a man of promise and a man of purpose," the sheriff said. "There is a very large hole in the heart of the Graham family. His death was tragic and unnecessary."
Robinson says the family did not want to comment about the story and says he has kept the family up to date about the latest developments in the case.
Sources say Baby Low is in custody. Ford is also in jail, charged in connection with last summer's hate-crime spree. Ford also declined to comment about this story.
Lockhart posted bond in March and is out of jail. She also declined to comment through a spokesperson.
Robinson says he is confident this investigation will be resolved, but he emphasizes he has not set any time limit for his detectives.
If you have any news tips, please e-mail 9Wants to Know Investigative Reporter Deborah Sherman at Deborah.Sherman@9NEWS.com.
(KUSA-TV © 2010 Multimedia Holdings Corporation)