While the brisk autumn air is a welcome shift from the past summer's stifling heat, a number of loose ends from the earlier season linger for area homicide investigators.
Gwinnett police continue to mine leads in six unsolved murders that occurred in the county over the summer. According to an analysis by The Post, which tallied homicides in Gwinnett between June 20 and Sept. 21 - the bookends of summer 2008 - no suspects in these cases have been publicly identified by authorities.
"All of the cases are active, open and (are being) investigated," said Sgt. Victor Pesaresi, the Gwinnett County Police Department's homicide squad supervisor. "We believe several (cases) will have arrests."
July had two unsolved slayings - including the police discovery of a Sugar Hill woman's body in her trailer - while August played host to a trio of unsolved murders. The killing of a Lawrenceville man, found stabbed to death in his garage, is the lone unsolved September homicide.
Gwinnett County District Attorney Danny Porter said the challenge of cracking a homicide case lies in the many variables investigators encounter.
"There are certain homicides that by their very nature are difficult to solve," Porter said. "When you get a stranger-on-stranger drive-by with no witnesses, it's difficult.
"Homicides don't come in any recognizable pattern ... you can have four easy ones in a row, and then a real who-done-it."
Staffing numbers also play a role in solving the murder puzzle, Porter said. The Gwinnett County Police Department employs eight homicide detectives - including a "cold case" investigator - and two unit supervisors, according to police officials.
Officials reported a record 50 homicides throughout Gwinnett last year.
"I'm sure there needs to be more investigators assigned to (the) homicide unit," Porter said. "There's really not enough personnel investigating these to devote the time needed."
The county saw 10 total homicides this summer, records show.
Police have arrested suspects in four of the slayings, including a Lawrenceville woman who allegedly shot her husband during a domestic spat. Another suspect, Devin Grell, 20, is accused of killing a close friend and seriously injuring a second person in a July shooting.
Homicide counts for summer 2008 dipped 47.4 percent compared to 2007, when 19 people were slain, according to the Gwinnett County Medical Examiner's Office.
In summer 2005 and 2006, a total of 15 and 14 people were murdered, respectively.
Hot, muggy weather is an oft-cited culprit in summertime homicides. Labeled "the heat hypothesis," trends show violent crimes, such as homicide, increase as the weather gets warmer, experts say.
Porter said the homicide trend typically nosedives as the weather cools, except for on holidays.