The written portion of the police testing process is meant to determine if the applicant possesses the foundational skills necessary to perform the work of a police officer. The police academy will provide training in search and seizure, probably cause, and reasonable suspicion. However, there is not time in the academy to teach basic skills such a math, spelling, grammar, and reading comprehension. It is expected that applicants bring these basic skills with them. A police officer who has such poor spelling that they cannot write a legible police report will find it difficult to do the job. Therefore, a police department says come to us with basic skills and we will teach you the rest.
Police written tests are not unlike college entrance exams such as an ACT or SAT. In general, police written exams cover reading comprehension, spelling, math, grammar, and analytical skills. The written test can also include a report writing test. Generally a passing score is 70% or better. Many departments have a study guide that can be beneficial.