"Incomplete and inaccurate" - that's the judgment about data on local gangs received from the Hamilton County Sheriff's Office and Chattanooga Police Department.
Researchers who spent six months compiling extensive information on gangs asked the two law enforcement agencies for data on every criminal incident for five years, with notation of which crimes are gang-related.
But researchers at the Ochs Center for Metropolitan Studies weren't satisfied completely with what the departments gave them.
Of the data the city provided, 16 percent had missing or incomplete demographic or gang information as well as inaccuracies such as incorrect or misspelled street names.
The sheriff's office submitted data only after several requests, and even then it was unusable, according to the Comprehensive Gang Assessment report.
"Programs implemented to combat gang formation, violence and crime depend on accurate benchmark data to compare pre-program and post-program results," the assessment states.
Law enforcement agencies in Hamilton County should exercise "best practices" in gang-related data collection and reporting.
"Officers should be educated on proper reporting procedures to ensure accurate information is captured," according to the report.
By the numbers
Chattanooga police made a concerted effort in July 2007 to begin tracking gang members and building an internal database of gang names, affiliations and street names of people they encounter in high-crime areas. But there still are inconsistencies in how the data is tracked, and not all gang-related crimes are tallied.
"I know it makes it easier and more intriguing for the media reporting on the incident if we hastily label incidents and people involved, but if we can't prove it initially, we can't label as such," said Chattanooga Police Chief Bobby Dodd. "For instance, if we have a shooting, a robbery or home invasion and can't prove immediately that there is gang involvement, we can't report in an official capacity.
"The problem I see is that, when we determine at a later date that there was gang involvement and we will list that information in the narrative of a supplemental report, a warrant or arrest report, those reports are not searchable when pulling strictly gang data," he said.
Still, researchers said the crime data presents a picture of the city's gang problem, which has become entrenched in some neighborhoods.
"Despite the weaknesses of the data, they do provide a valuable snapshot of the location of gang crime in Chattanooga," the assessment states.
From 2007 to 2011, Chattanooga police documented 1,391 gang members and 654 gang-related crimes.
At the Hamilton County Sheriff's Office, raw data shows dates and addresses and types of crimes, but there is no indication which gang was involved and little demographic information on suspects or victims.
Sheriff Jim Hammond, who has said publicly that gangs are spreading to more rural parts of the county, could not cite figures to support comments he has made in the past year.
"No, I don't think I can give you any hard numbers. I think it's one of those things you get a gut feeling that you're going on some calls that are gang-related, perhaps," he said.
National studies suggest that he's likely right that gang members are moving out to more rural areas.
The office's fugitive unit, other detectives and the narcotics division, which added a gang investigator a couple of years ago, have noticed an increase in gang members and gang-related crimes in rural areas, he said.
In the 2010 annual report from the sheriff's office, 54 people were listed as validated gang members, but there was no mention of gang-related incidents outside the schools.
"We don't think it's reached the place of where we should be overly alarmed by it," Hammond said. "We're just cognizant of it in tracking some of these people."
Ken Chilton, president of the Ochs Center, said better data will be needed to tackle the gang issue at all levels.
"Data on the front end, if it's bad, we're not going to have good outcome measures to see if things are changing or not," he said. "It can either skew it and make the programs look great or make them look bad."
Hammond and Dodd said their departments need more direction after learning that better recordkeeping practices are needed.
"I'm not sure what they mean by 'best practices,'" Hammond said.
Dodd said he is "a little disappointed that our data submissions were lumped in with all law enforcement and characterized as 'inaccurate and incomplete.'"
"From discussions that I had midway through the assessment with Dr. Chilton, it was my understanding that we had provided the lion's share of the law enforcement data, and he seemed to be satisfied with the data that had been collected. We will take the criticism and learn from it," Dodd said.
The assessment can be a useful tool for law enforcement to combat gangs if departments follow the suggestions, said Bruce Ferrell, president of the National Alliance of Gang Investigators' Associations.
The group represents 20,000 investigators in 43 states and offers free training for law enforcement when coordinated through the National Gang Center.
"A lot of it's just training," he said. "That's why the assessment is so important. It tells you where the issues are and helps you identify where to place your resources."
Ferrell worked for the Omaha Police Department for 23 years, including nine years as a gang investigator. He has been reading news stories on Chattanooga's gang problems for more than a year now. He said patrol officers and investigators must be trained on what to look for and encouraged to document gang incidents and other data. Chattanooga officers receive gang training on an annual basis.
"Guys need to be reminded, 'These are the guys [gang members] who are operating. Here's their signs and signals. Here's who's active. These are high-profile people. So if you run across them, fill out the field card,'" Ferrell said. "These are the people influencing more crimes."
Omaha police use gun data and crime data as well as maps of suspects' addresses and crime locations to learn where to place resources.
"By tracking the firearms and gang members, we start putting a picture together at the investigative level and patrol level of what's going on in the street," he said.
The gang task force applied for a grant to keep track of gang-related crime data among all law enforcement agencies in Hamilton County. "If we don't get this grant, we still need this [crime analyst] position," said Boyd Patterson, the city's anti-gang coordinator.
Dodd and Hammond are waiting to see if that grant comes through.
"This will be helpful not just for prosecution efforts, but also for the strategic planning of limited resources," Dodd said.
In the meantime, there are no immediate plans to change protocols for collecting data at the departments.
"My position is: We're a member of the [gang] task force. Boyd [Patterson] is the czar, so to speak," Hammond said. "If he calls me up and says, 'Let's take this information and sit down at the round table and talk about where we go from here,' we are ready to do that."