An investigator is observing a subject from a public park. The subject is inside their private home with curtains open. Is capturing video footage of the subject inside their home from the public park generally permissible?

1. Only if the subject is engaged in illegal activity.
2. No, because it always constitutes a breach of privacy.
3. Yes, if the subject has no reasonable expectation of privacy due to visible actions from a public vantage point.
4. Only if the investigator has a search warrant.