It’s illegal because the Empire State Building is private property and a heavily secured landmark, so climbing it without permission is trespassing and can trigger serious criminal charges. It’s also illegal because the act creates major safety risks for the climbers, workers, tenants, visitors, and police, which is why people who did it were arrested this week.

Why the law applies

A few things make it illegal at once:

  • Trespassing: Entering restricted parts of the building without authorization is a crime.
  • Public safety risk: A climb that high can endanger people below and require emergency response.
  • Security rules: Famous landmarks have strict access controls, and breaking them is treated seriously.
  • Possible additional charges: Reports say recent climbers faced multiple felonies and misdemeanors, not just one simple trespassing count.

Why it’s treated so seriously

The Empire State Building is not treated like a normal rooftop. It has observation deck access for visitors, but the spire and other restricted areas are off-limits; the building’s rules also prohibit certain disguises like masks and costumes. Recent reporting says the climbers were taken into custody after reaching the top and unfurling a banner, showing how quickly an illegal climb turns into a policing and safety issue.

In plain English

You can visit the building legally through the public observation areas, but climbing the exterior without permission crosses into criminal trespass and dangerous conduct. Think of it as the difference between going to an open museum hall and breaking into a locked maintenance shaft: same building, very different legal status. TL;DR: It’s illegal because it’s unauthorized entry onto restricted private property, and authorities treat it as both trespassing and a serious safety threat.