Data and methods

Every number on this site comes from a government open-data portal or an official city document, and each page names its source.

Ticket counts

• New York City: NYC Department of Finance parking and camera violations, one row per summons, counted by violation date. Red-light camera = violation code 7, school-zone speed camera = code 36. We count summonses by location and month on the city's portal and never download plate numbers. A few locations can't be pinned to a map; they count in city totals but don't get their own page.
• Chicago: City of Chicago red-light and speed camera violations, per camera per day since July 2014. The city holds back the most recent 14 days.
• Washington DC: DC's automated safety camera monthly counts. Warning-period notices are shown as warnings, never as tickets. A few dozen retired cameras have no published location and appear only in city totals.
• San Francisco: SFMTA's speed-camera citations and warnings (daily, per camera) and red-light camera citations (monthly, per intersection).

Months and "last 12 months"

A month counts only when the source's data covers all of it. "Last 12 months" means the 12 complete months ending with the newest complete month in that city's data, so cities can differ by a month or two.

Fine estimates

Estimated fines multiply tickets by the posted fine from the city's official schedule. Where fines depend on speed and the data doesn't say how fast each car was going, we use the lowest posted fine and say so. These are estimates of tickets issued, not money collected: some tickets are dismissed, reduced or never paid, and late penalties raise others.

Warnings vs tickets

Warnings and tickets are always counted separately and never added together.

Camera locations

Locations come from each city's or county's own map data. OpenStreetMap reports (© OpenStreetMap contributors, ODbL) fill the national map. When an OpenStreetMap camera sits within 30 m of an official one, the official record wins.

Sources and refresh dates

Downloads

• New York City: every camera location (CSV)
• Chicago: every camera location (CSV)
• Washington, DC: every camera location (CSV)
• San Francisco: every camera location (CSV)

Each camera page also has its own monthly CSV. You're welcome to reuse the numbers with a link back; the "Cite as" line on each page gives the exact reference.