The LAPD's helicopter fleet logs roughly 18,000 flight hours each year, providing backup for ground officers during pursuits and arrests, and directing the deployment of officers at crime scenes. The department maintains a lot of statistics about where the choppers go and what they do, but it doesn't analyze the data to determine the helicopters' effectiveness as a crime fighting tool.
Last year, police choppers helped set more than 1,500 perimeters. That’s when a helicopter positions ground officers to surround a crime scene. The air division places a high priority on getting to a scene first. That happened 16,000 times last year. Choppers served as aerial backup for officers more than 4,000 times.
“That advance notice is very vital to the officer as they’re responding because it gives them an opportunity to plan and it minimizes the lag time where they have to come up and make a decision on how they are going to encounter the invididuals," says Sergeant Tim Torsney, who heads up ground patrol units in the Devonshire Division.
But the numbers can’t answer all of our questions, such as whether a chopper can make the difference between a suspect getting away and being arrested.
The most recent LAPD statistics show that helicopters “assisted” in one out of seven felony arrests in 2011. That means choppers gave ground officers information that could have helped in making the arrest.
But it’s hard to know how crucial that information was to making that arrest. Lieutenant Phillip Smith is the Air Division’s assistant commander. He leaves that assessment up to the ground troops.
“So the onus is now upon the different divisions to say, we were successful," says Smith. "Now whether it was the air support unit solely or the ground resources solely, or a combination of those, that’s up to them to determine. We just go out and perform the mission.”
The most recent data show that LAPD choppers recovered 51 stolen vehicles in 2011 by identifying them from the air and alerting ground officers. Helicopters helped ground units recover another 847 stolen vehicles. But combined, that’s only six percent of the 14,810 vehicles recovered by the LAPD within the city that year.
The air division reviews its statistics every couple of months, but it never analyzes those numbers to determine the helicopters’ effectiveness.
A lot of cops say you can’t measure effectiveness with statistics alone. Greg MacDonald is a flight officer for the chopper fleet, but before that he spent ten years as a street cop. He remembers how he always felt relieved to hear the buzz of an airship when he called for backup.
“A lot of times when you put it out on the radio you’re like, ‘God, are people hearing me? Are people coming?' says MacDonald. "But then when they hear the helicopter, you’re like, ‘Okay…I know the troops are coming.’”
There’s been little recent scientific research on police helicopter effectiveness. A 1998 US Department of Justice study of Miami and Baltimore concluded that choppers did help during pursuits, both in protecting the public and in catching suspects.
But police officials say one of the helicopters’ key assets is the hardest to measure: their deterrent effect.
Not everyone agrees. Dr. Geoffrey Alpert was co-author of that 1998 study in Miami and Baltimore. He believes helicopter patrols don’t deter crime.
"I mean that’s the whole thing about random patrol," says Alpert. "You see a police car and it’s the same thing. You hide, he goes around the block and you go back to your breaking and entering.”
But the police point to the only research KPCC could find on LAPD choppers -- a Jet Propulsion Lab study carried it out in the late 1960s.
Two areas were tested: the USC area, which includes the Coliseum, Sports Arena and Shrine Auditorium, and the western part of the San Fernando Valley.
The study attributed lower property crimes such as motor vehicle thefts, burglaries and even lower robberies to helicopter patrols.
“There’s no doubt that if you put yourself in the criminals’ mindset, that if you are about to break into that car to steal, break in that house -- and all of a sudden you hear that thump, thump, thump, you hear that helicopter -- you’re probably not going to break in," says the Air Division's Lt. Smith.
The key word is “probably.” You’d have to survey criminals to see if a helicopter ever changed their minds about breaking into a car or committing some other crime. That hasn’t been done, so we're left to speculate about what criminals are thinking.
In the end, Lt. Smith says his bosses are convinced that the fleet is worth its nearly $20 million-a-year price tag.
“Our department brass for the LAPD, because they’ve risen through the ranks and they’ve seen the effectiveness of the helicopters, they have been a huge proponent for us," he says.