Ethical and Legal
Computer Misuse Act
Contents
Computer misuse is using a computer system, or the data stored on it, in a way that is not allowed or without permission. Gaining unauthorised access to a computer system is a criminal offence.
Unauthorised access
Unauthorised access means gaining entry to a computer system, or viewing the data on it, without permission. People usually call this hacking, and it is a crime even if the person only looks and changes nothing.
Access is still unauthorised when the login is genuine but the person using it has not been given permission for what they are doing. For example, a chess club gives its members the password for the club's shared account so they can book practice rooms. A member who then uses the same password to open the club's folder of membership payments has still gained unauthorised access: the login works, but permission covered the room bookings only.
Unauthorised modification of data
Changing, editing or deleting data without authorisation is also computer misuse. It matters because the owner of the data can no longer trust it: a set of results that has been quietly edited can make a whole competition unfair, and a deleted file may be impossible to rebuild.
| Action | Allowed or misuse? |
|---|---|
| A librarian logs in to the school library system to add a new book | Allowed, because the librarian has permission |
| A customer guesses a shop worker's password and reads the shop's stock file | Misuse, because there is no permission |
| A club member deletes a rival club's list of results | Misuse, because data is changed without authorisation |
Any system, any data, anyone
The law protects any computer system and any data, not only personal data, so a school's timetable file or a shop's stock list is covered just as much as names and addresses.
Unauthorised access can be carried out by people inside an organisation as well as by external hackers, because a badly behaved employee may already hold a login. Misuse, hacking and unauthorised access can all describe the same illegal activity, so any of these terms may be the right word in an answer.