Pursuant to the New York City Administrative Code, it is the duty of the owner of real property adjacent to any sidewalk to ensure it is kept in a reasonably safe condition. The failure to reasonably maintain a sidewalk can leave the owner of the adjacent property liable for any injury that occurs due to the sidewalk's deteriorating condition. A failure to maintain a sidewalk in a reasonably safe condition includes but is not limited to: The negligent failure to properly install a sidewalk near the property The negligent failure to reconstruct a walkway once it becomes defective or unstable Negligently failing to repave sidewalks that are cracked Failure to repair any defects Not replacing defective sidewalk flags Failure to remove snow, ice, dirt or other materials from the sidewalk