Online surveillance tools permit investigators to track the activities of individuals in real-time. They may include cameras, microphones, GPS trackers, and biometric scanners such as fingerprint and iris scans. They could also contain software that spies on computer activities, for example keyloggers.

The application of these tools has serious legal implications. They can violate human rights and must be subject to clear legal frameworks to protect privacy. These frameworks must define the grounds for their use and specify necessary authorization procedures, which include judiciary oversight. They should also stipulate the limits of data collection and retention.

A lack of transparency in the use of these tools can also be a problem because it can foster the perception of self-censorship and fear in people who are concerned about being watched. The monitoring of social media to detect threats, without any suspicion of wrongdoing, can also result in a huge amount of ineffective information. This can obstruct resources and information for real security concerns for the general public.

Although these tools can offer law enforcement agencies substantial investigative benefits, they must be subject to clear legal frameworks that guarantee the rights of individuals. The laws must specify the grounds for their use, establish the required authorization procedures and set limits on the storage and collection of data. The tools should be subject to judicial oversight, as an independent judicial review may help to prevent misuse of surveillance technology. In addition regular reporting and disclosure of information can improve trust and aid in public debate about the proper extent and limitations of these tools.