Academic style guide
26 Using the passive voice
General
Whether to use the passive voice or the active voice is a topic of most guidebooks on scientific writing. Overall we can say that the active voice is more concise, more direct and easier to read. However, in your academic studies you will often come across and are required to use the passive voice. For example:
The passive voice is used because technical reports or scientific manuscripts are impersonal. The content is separate from the personality of the writer. Even though this often leads to wordy formulations such as It is known… rather than We know…(three words instead of two), you will see the impersonal passive voice in many publications.
However, it is not merely a question of changing an active into a passive sentence: in the methodology section for example the passive voice serves to emphasise the process rather than the agent such as in Twelve experts were interviewed to… The emphasis here lies on the experts and not on the person who conducted the interview.
Language focus