Police serve as two-wheeled referees for a three-way rivalry

Sergeant Kathleen Murphy checks in with Patrolman Oswaldo Ortiz. (ethan gilsdorf for the boston globe)

Drivers like to gripe about cyclists' failure to follow the traffic code. "They behave by their own rules," drivers complain.

"Uh, hello?" pedestrians complain when bikes and cars whiz through crosswalks. "Do you even see me?"

Then there's the complaint that police unfairly target cyclists while ignoring vehicles that side-swipe them and park in bike lanes. "Drivers don't respect our right to be in the road," cyclists say.

Meanwhile, the ranks of law-abiding bicyclists seethe when renegade riders give them a bad name.

Rival road warriors on the urban streetscape have their turf battles. Caught in the middle is Sergeant Kathleen Murphy. As head of Cambridge's Community Relations Bike Patrol Unit, she keeps the peace on the front lines of conflict among motorists, pedestrians, and cyclists.

"It's like a love triangle," Murphy said. Then she corrected herself: "More like a love-hate triangle."

Murphy, who walks, rides, and bikes, can sympathize with the needs, and misdeeds, of all three sides. "It's hard to keep everyone happy," she sighed.

Fueling the feuds is the unequal price each side pays for breaking the law. Jaywalkers in Cambridge face a mere $1 ticket. Commit any bicycling violation, no matter how severe, and pay $20. But drivers are hit with much stiffer penalties: running a red light costs $100, blowing through a crosswalk nets a $200 fine.

I caught up with Murphy at her desk at the Western Avenue police station in Central Square. A lifelong Cambridge resident who grew up near Fresh Pond, she talked about her 25 years on the force and her eight years with the bike patrol.

Since 1996, Cambridge has staffed a "cops on bikes" unit. Nine officers plus Murphy regularly patrol on two wheels, and about 60 members of the force are trained to ride. Typically, two to four officers are out at any given time (often in winter, too). The unit has an SUV equipped with a bike rack, so cops can drive to a neighborhood, patrol on bike, then duck into the vehicle if the weather gets nasty. Nowadays, all new recruits receive bike-riding training at the academy. Even some Cambridge parking control officers use bikes. "They can cover a lot more ground that way," she said.

Her unit's goal isn't to rack up tickets so much as be a community presence.

"When we are out doing bike enforcement, it's not about making money, it's about education," she said. Murphy said she focuses on blatant moving violations, and monitors pedestrian and bicycle accidents to understand their primary causes. Number one on her list is dooring; as many as eight bike vs. car door accidents are reported per month. "It's like hitting a brick wall. I've been doored," said the 50-year-old grandmother.

Her approach to prevention is a "two-fold educational piece." One, teach drivers to look before opening their doors. Two is to remind bikers to keep the proper distance from parked cars. "You almost have to have a near miss to get educated."

Later, Murphy and I grabbed our bikes, put on our helmets, and pedaled down Western Avenue. As we wended our way through the side streets of Cambridgeport, Murphy talked about the advantages of patrolling on two wheels.

"We are more approachable," she said.

Another big advantage: the stealth-like bike patrol's element of surprise. "You're quiet, you can cruise up a driveway or through a park," said a unit member, Officer Oswaldo Ortiz. Criminals "aren't looking for cops on bikes. They're looking for patrol cars."

We caught up with Ortiz, a 14-year veteran, after his appearance at a summer day camp at Graham and Parks School to promote bike safety. Along with patrolling, Ortiz and Murphy visit nursing homes, run basketball tournaments and attend bike committee meetings.

But the job isn't all block parties and story hours. One disadvantage: not being taken seriously. Plus, Murphy admitted, on a bike "it's hard to pull a car over." Her bikes don't have blue lights (and no, she has never fired a gun from the saddle).

Where Mass. Ave. crosses Wendell Street, we watched as a car stopped far past the white line. "She should have stopped back here," Murphy said, but didn't cite the driver. Her unit mostly pinpoints cyclists and pedestrians.

As we biked around, she pointed out the hot spots. For example, at Mt. Auburn Street and Putnam Avenue, a biker had recently ignored a crosswalk, striking and injuring an elderly woman. Murphy's explanation? "The biker zoned out." Another perennial bike-ped problem spot: 77 Mass. Ave., in the heart of MIT's campus.

Murphy was clear: The law states that bicyclists must follow the same rules of the road as other drivers, and that includes stop signs, signaling and using lights. "You have to have at least a reflector in the back and a strong white light in the front," she reminds riders. "It's the law." So is a helmet for ages 16 and under.

But Murphy's rulebook has some flexibility. At a red light, she recommends bikers wait just beyond the white line to be more visible to drivers. "Motorists just aren't looking for bikes." On low-traffic, noncommercial streets, she'd rather see bikers ride slowly on the sidewalk than go the wrong way down a one-way street.

Mainly, the sergeant worries for the safety of all road users - especially bikers who still ride "the old way," against traffic, rather than with the flow. "It would be good if to ride a bike on the streets you had to take a class," she wished. That, at least for now, is not the law.

If nothing else, the department's patrol unit furthers the cause of what Murphy calls "the whole bike philosophy." Folks approach her and say, " 'Wow, I see a lot more people on bikes,' " she said. Having officers on patrol "really does prove that we have bikes out there."

A big day for bikes

Boston's largest city-sponsored sporting event is Hub on Wheels, now in its fourth year and a cornerstone of the Mayor's Boston Bikes effort to open the city to cyclists. Next Sunday, an estimated 5,000 bikers will have Storrow Drive and Comm. Ave. all to themselves.

"We're excited to have roads 100 percent closed to traffic with phenomenal views," said Nicole Freedman, the city's director of bicycle programs. "People discover Boston, places that are strikingly beautiful and places to ride for the future."

It's all for a good cause, too. The event's 10-, 30- and 50-mile rides, not races, around the city will benefit the school district's technology programs.

"This is a ride for all of Boston to see all of Boston," said Freedman. Basic registration, $45. Info online at hubonwheels.org.