On a cool, sunny morning in Brooklyn, rush hour on Prospect Park West can look like the apple of a traffic engineer's eye. Streams of cars ease off Grand Army Plaza, stop at a light at Carroll Street, and move smoothly on, mostly undeterred by even the occasional double-parked school bus. Pedestrians leaving luxury apartment buildings head north to the nearest subway stop. And, along the street's eastern edge, there is its most controversial feature: the two-way bike lane installed almost a year ago.

Riding there, on one such morning, were women with messenger bags, men in business clothes, children with school backpacks. A small boy rode by on training wheels. A father on one bike had a daughter sitting behind him and another riding a scooter alongside. The lane was, at first glance, an unlikely source of controversy at all. Successful by all reported statistical measures, it is the result of a years-long governmental outreach process, popular with the local community board and in its neighborhood, Park Slope, as a whole.

The lane's short history has been troubled, though, in large part because of a few of its high-profile neighbors. They include Borough President Marty Markowitz, Dinkins-era deputy mayor Norman Steisel, and Louise Hainline, a Brooklyn College dean who lives in a Prospect Park West penthouse and monitors the lane from a spy camera. No lane opponents have raised more eyebrows in city political circles, though, than Iris Weinshall – a Prospect Park West resident, a former city transportation commissioner, and the wife of Charles Schumer, one of the most powerful politicians in the country.

Weinshall, who is now a vice chancellor at the City University of New York, responsible for facilities planning and construction, has kept a low profile on the bike lane issue lately. She did not respond to a call or an emailed list of questions for this article, and the nuances of her current thinking are hard to know. But her close association with a group that is suing the city over the lane, and her few public statements on the project, all of which were negative, have given the lane opposition one of its most important allies.

In December, City Council member Brad Lander told The New York Times that Weinshall and Steisel had met with him to advocate tearing the Prospect Park West lane out. And along with Steisel and Hainline, Weinshall signed a letter to the paper that month that cast doubt on the DOT's statistics that showed the lane was working. The letter accused the department of a "lack of credibility," and, although Weinshall and the other two authors said they support bike riding in principle, they also suggested that it should require a special license.

A note accompanying the letter identified the authors as members of Neighbors for Better Bike Lanes – the group that, along with an organization calling itself Seniors for Safety, is behind a lawsuit seeking the lane's removal. The suit's first hearing in court is scheduled for June.

In recent months, the lawyer representing the bike lane opponents has said Weinshall is not a party to the suit. And Hainline, one of the letter's other two authors, said in a short recent phone conversation that questions about Weinshall are misdirected. "The bike lane issue on Prospect Park West is about anything else except Iris Weinshall," she said. "She's not the people who are centrally involved in this. It's a gossip story."

Weinshall's advocacy, though, goes back further. The Daily News reported last July that she had attended a strategy session against the lane, and the Post said in February that Schumer himself had lobbied against it in private conversations with City Council members. In October 2009, in a letter obtained by the transportation advocacy site Streetsblog, Markowitz wrote the DOT a letter opposing the lane, noting pointedly that he was "joined in this request by former DOT commissioner Iris Weinshall, who absolutely agrees that the installation of a two-way, barricaded bike lane would cause incredible congestion."

(That congestion never materialized, and opponents now focus on what they say is the lane's danger to pedestrians, and on the process that led to its creation, which they say should have been more inclusive.)

In Weinshall's public comments, she has said that she is not against bike lanes in general – that, in fact, she oversaw the construction of many of them. Even her critics concede this point, though they argue she could have done more. Her advocacy against the lane just outside her front door, though, raises the opportunity for a closer look at her record.

A steady manager

When Weinshall took over as Department of Transportation Commissioner in September 2000, appointed by Mayor Rudolph Giuliani, it was the first job in her long administrative career that dealt with transportation. She had graduated from Brooklyn College and later earned a master's degree in public administration from NYU. She worked in high-level deputy jobs at the New York State Urban Development Corporation, the city Department of Environmental Protection and the Department of Citywide Administrative Services.

At the DOT, she took over a department with a range of responsibilities, including repair of hundreds of large and small bridges around the city, maintenance of all of the city's streets, and the operation of the Staten Island ferry.

Sam Schwartz, a deputy commissioner at DOT in the 1980s and the founder of Sam Schwartz Engineering, says Weinshall was known as an effective manager. In the time before she came into office, he adds, "there were some really turbulent years in the department and it wasn't functioning that well. I think she did give good stabilization to the department."

Regarding Weinshall's resume, he notes, "I think her experience was not in transportation when she became commissioner, but she was a fast learner, and she picked up a lot."

Her tenure, Schwartz noted, also was marked by a decline in traffic fatalities. According to Mayor's Management Reports, 423 people were killed in traffic accidents in the city in the 1998 fiscal year, 407 in 1999. The number dropped steadily through most of Weinshall's time in office, falling to 300 in 2005 before rising slightly to 310 in fiscal year 2007, her last in office.

The city also did install bike lanes under Weinshall – though for a long stretch, the number of miles of lanes decreased every year, from 32.2 in 2003 to 23.1 in 2004, 11.8 in 2005 and 3.5 in 2006. After that steady year-to-year decline, Weinshall's department put in 41.8 miles of lanes in her last year, fiscal year 2007. According to the management report, it was the largest number of lanes installed in one year since fiscal year 2000 – the year before Weinshall took charge.