Kōtarō Fūma

is a tokubetsu jōnin that serves as the head of the Konoha Military Police Force.

Abilities
Being the head of the Konoha Military Police Force, it can be assumed that Kōtarō is a talented shinobi. He is very responsible for his work and skillfully manages his subordinates, while personally delving into all the crimes, knowing everything about everyone who has even the slightest part in the committed action.

Weapon
As a member of the Fūma Clan, he carries a Fūma Shuriken on his back that he is presumably skilled in utilising. He also has a tantō with a bandaged hilt in a sheath on his right leg.

Genin Mission Arc
Kōtarō appears in this arc.

Byakuya Gang Arc
Kōtarō appears in this arc.

Mitsuki's Disappearance Arc
Kōtarō arrests three wanted criminals from the Bingo Book after a new member of Team 15, Tsubaki Kurogane, defeated them.

Mujina Bandits Arc
Kōtarō was part of the briefing of Team 7's mission to infiltrate Hōzuki Castle to verify the information about the Mujina Bandits offered by Kokuri in exchange for protection. Despite getting Kokuri's information, after several months of investigating, Kōtarō and the police force were no closer to bringing down the Mujina Bandits.

When Nezumi Kaitō steals jewelry in the village, the police fail to catch him and ask Team 7 for help. Together they corner Nezumi, but he manages to hide among the drunks in the alley. Kotaro arrests everyone as he suspects the thief is among them. However, due to lack of evidence, he has to release the detainees. Not believing any of them, Kōtarō puts all the detainees under surveillance and soon finds out that Nezumi fed the stolen jewels to the cat. Together with Team 7, the police corner Nezumi when he tries to kill the cat and take the jewelry, and then arrest him.

Later, when the police determined that Kaneki, president of the Kaneki Corporation, was being targeted by the Rain Killer, Kōtarō assigned Team 7 to work with him on guard duty.

Kara Actuation Arc
When learning of Kara and concerned that there might be a spy in the village, Naruto talked with the various officials including Kōtarō about closing off the gates to the village. Kōtarō supported the idea, mentioning previous incidents resulting from infiltrators, and noted there were indeed visitors who disliked Konohagakure.

Great Sea Battle of Kirigakure Arc
Kōtarō worked alongside Team 7 in investigating a series of attacks to former Wind Release-using shinobi, gathering information from similar attacks in other villages. Together, they discovered that a person of interest in another series of crimes was likely a target, and uncovered the real reason behind the attacks by Kodama and Hibiki.

Trivia

 * Kōtarō's full name is derived from the famous shinobi Fūma Kotarō. Masashi Kishimoto originally designed Gaara with this name in mind.