The NYPD might have to start considering weather, road conditions, and even jay walking before penalizing a driver for harming pedestrians and bicyclists.

Queens Councilman Rory Lancman plans to introduce legislation amending the "Right of Way" law, which passed as a key part of Mayor Bill de Blasio's Vision Zero street safety agenda.

Lancman said he was dismayed that NYPD officials were unable to explain how officers apply the law that creates a misdemeanor crime against motorists who fail to "exercise due care," as well as yielding to pedestrians, when injuring or killing someone who has the right of way.

But street safety advocates ripped into Lancman's effort as simply a way to put the brakes on enforcing the law against drivers who kill and injure others on the road.

"We're not weakening the law," said Lancman, who called himself a Vision Zero supporter.

Instead, the bill "will actually strengthen the law," he added. "The criminal law is unclear and ambiguous, is difficult to enforce and ultimately uphold in the courts."

Paul Steely White, director for the advocacy group Transportation Alternatives, called Lancman's legislation an "affront to safety" and the NYPD, adding it questions officers' competence in handling these investigations. He said the law is rarely used to arrest drivers and that the law already accounts for jaywalking, adding it's "irrelevant" as the law is solely applied in cases when the pedestrian has the right to cross.

"If a driver slams into a person who is walking in a crosswalk with the right of way, that is, by definition, failure to use due care," White said. "If it is raining or snowing, lawful drivers know that they must slow down and drive more carefully."

Relatives of people killed by drivers are opposing changes to the Right of Way law, including one bill to exempt MTA bus drivers.

Amy Tam-Liao and Hsi-Pei Liao, constituents in Lancman's district whose daughter Allison was killed by a driver making a left-hand turn, are planning to protest in front of his Queens office.

The amendment to the law would require NYPD to consider a host of factors in its investigation, such as visibility, lighting, street design, and vehicle malfunctions.

"Adding a provision to the bill to require an analysis of due care will penalize drivers who hit pedestrians out of recklessness and gross negligence, while sparing drivers when accidents are caused by poor road conditions, bad weather and scofflaw pedestrians," Lancman wrote to his colleagues to rev up support.

In a letter to Lancman, NYPD Chief of Transportation Thomas Chan explained an arrest of a driver under the Right of Way law is made based on the "full consideration of all the elements of the crime, including the failure to exercise due care."

But Lancman said the letter did not address his concern. The NYPD defined "due care" as the conduct people will use in a situation who are "looking out for the safety of others."

"When the NYPD can't articulate how it is applying the law that the Council passed, that makes me nervous," Lancman said.

Updated, 3:13 p.m., 5/21/15.