WESTMINSTER, Colo. - Horrific crimes. Few clues for investigators. Cities in fear.
There are some similarities between the investigation into Jessica Ridgeway's murder and Washington, D.C.'s infamous serial sniper case a decade ago.
Just like the Ridgeway investigation, serial sniper investigators had few clues initially on who was behind a string of random shootings that left 10 people dead.
Michael Bouchard, a former agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives, helped lead the sniper investigation.
"These kinds of cases are one tip away from being solved," Bouchard told 7NEWS.
In October 2002, much of the Washington, D.C. area was gripped in fear over the sniper slayings, unsure of when the next shooting might happen.
The Denver area is experiencing similar fear over Jessica's killer, who police have called a 'predator.'
While fear usually makes people more aware, Bouchard says it can also work against an investigation.
"Fear tends to make people stay indoors, in some cases, and become sheltered so they're not normally out and normally wouldn't see the things that they'd see on a day-to-day basis," Bouchard said.
Investigators in the Ridgeway case have said they won't be frequently commenting on developments in the hunt for Jessica's killer. Bouchard said this is done by design, because investigators know the killer could be watching news coverage.
"They have to be very careful to balance what the public needs to know and what they think the public can do to help them solve this case," Bouchard said. "It's a delicate balance of what information you release."
Bouchard said it is likely investigators are trying to get a clearer picture of who was in and around Jessica's neighborhood the day she was abducted. He said they'll be doing that in ways visible and invisible to the rest of us.
"In any case, people should trust law enforcement. Things may not be moving quick enough for people, but I can say first-hand that all law enforcement people take it to heart and don't want to see any more people killed or injured," Bouchard said.
In the sniper investigation, arrests were made after a man spotted the vehicle the suspects were driving in a Maryland rest area.
By encouraging people to call in tips to police, Bouchard said the public will likely help bring justice for Jessica.
"Every lead is important," Bouchard said. "There's nothing you should hold back."