Privacy laws vary with the legal jurisdiction and the answer to this is completely dependent on where you reside. But in general terms, you are not permitted to record an image or voice of an individual without their permission. There are exceptions to this, of course. Exemptions may include monitoring for security purposes, recording individuals during a crime, and gathering evidence of criminal activity. Generally speaking, these exceptions fall under the umbrella of security, law enforcement, and certain media applications. Some images are exempt from privacy regulations and can be freely published in a newspaper or shown on television because of their journalistic content. In some cases, a court order is required to be allowed to make recordings of an individual. Sometimes there is a very fine line between what is acceptable and what is not. In many jurisdictions, such activities fall under copyright law. This might seem a little odd at first glance, but does make sense. A person who records your image or voice without permission and then uses it for personal gain may find themselves in trouble. They could be required to turn over all recorded material, the profits from their sale, and face a punitive fine. This is the reason that professional photographers often ask a subject to sign a model release form. This grants them permission to use a recording of the subject for personal gain, under the conditions agreed to in the release form. It is always a good idea to ask a person for their permission to record their image or voice. People often consider such activities to be a violation of their privacy. In Canada, for example, recent changes to federal privacy legislation have substantially changed the way personal information is handled by individuals and corporations - there are now much stricter controls on the handling of such information.