Dietz was a male operative of Section 31 in the 24th century.

In 2379, Dietz was responsible for monitoring the Federation's situation with Tezwa which included listening in on conversations between Federation President Min Zife and a group of Starfleet admirals giving orders to Captain Jean-Luc Picard and to conversations between Presidential Chief of Staff Koll Azernal and Bilok, the Deputy Prime Minister of Tezwa. He also carefully monitored the movements of Nelino Quafina.

Under orders from his supervisor L'Haan, towards whom he harbored romantic interest, Dietz was prepared to destroy the entire planet of Tezwa if the USS Enterprise-E failed in its mission. Although L'Haan and he shared similar opinions on policy and was not squeamish about destroying planets, he disliked such heavy-handed methods, preferring subtlety. Carrying out this order became unnecessary when Worf was able to obtain the Fleet Command codes which allowed the Enterprise to take control of the entire Klingon fleet. (TNG novel: A Time to Kill)

Along with his fellow operatives, Dietz continued to monitor the actions of Azernal and Quafina, including their hiring of the merchant freighter Caedera. He was responsible for activating the Orion Sleeper. Once Zife's illegal actions were known to a select group of Starfleet admirals who forced him to resign, he, along with Vasily Zeitsev and L'Haan, was responsible for escorting Zife to give his resignation, and then executing Zife, Azernal, and Quafina. (TNG novel: A Time to Heal)

Known members and associates of Section 31
Primary universe Olivia AkomoCaliq AzuraJulian BashirLance CartwrightColeControlDietzMatthew DoughertySarina DouglasFranklin DrakeEnderbyDarwyn FrielMatthew HarrisJedburghKarimBendes KettaractKen KitsomKo Ji-hoonJhun KulkarnoL'HaanPeter LawrenceLeeEthan LockenRoberta LukeMerraErovan M'RillOlim ParraTinh Hoc PhuongErik PressmanRamirezParvati RaoMalcolm ReedTomas RoederWilliam RossConnaught RossaSakonnaLuther SloanEric StillwellAubin TaborMalla TancredaKestellenar th'TeshinaalCharles Tucker IIIDavid WebbMarcus WilliamsVasily ZeitsevCortin Zweller 31
Kelvin timeline Thomas HarewoodJohn HarrisonRobert AprilAlexander MarcusYuki Suluunnamed Section 31 personnel