If you're looking for manga similar to Gesu no Police, you might like these titles.
A manga which follows the lives and experiences of a couple of female police officers.
A cute, fun spin-off of Fairy Tail! The Magic Police can handle any case! A heartwarming police story!! The members of Fairy Tail are now police officers! Rookie cop Lucy has just been assigned to Team Fairy Tail, a special unit of the Magnolia Police Department. Together with its completely over-the-top members, including Natsu, she'll protect Fiore City from wrongdoers like motorcycle gangs, stalkers, bank robbers, and masked thieves!! The curtain rises on a Magic Police story featuring the all-star cast of Fairy Tail!
Tetsunosuke Yamabuki enrolls in the police to follow in his fathers footsteps. Some events lead him to discover that his father might have had links with a secret branch called the death brigade, and he is led to enter it himself. Wacky adventures and hilarity ensues.
Riki has been reassigned to a different department in the police department. Riki, disliking paperwork, is glad to hear that he doesn't have to do any paperwork since his new assignment is to test drive a new vehicle secretly invented within the department. The new vehicle, however is beyond Riki's imagination; a talking car covered with a mascot girl on all sides. The car is a "Patrol Car with Artificial Intelligence & Technical Illustration" named Pattie 2000 and it talks like a human. A car that can talk, react to situations quickly, and has all sorts of technological advancements such as maps appearing on glass... and it can transform into a girl!?!? Technology is grand, isn't it?