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Stephen Leach was first officer of the USS Stargazer under the command of Captain Daithan Ruhalter. In 2333, he held the rank of commander.

Although Commander Leach was a proficient Starfleet Officer, he did not fit into the dynamic command structure aboard the Stargazer and Captain Ruhalter found a deep affinity in second officer, Lieutenant Commander Jean-Luc Picard.

Having observed that Captain Ruhalter would often confer with Picard in command situations, as well as assigning him to his personal detail when speaking to high ranking officials, Commander Leach did not hesistate to relay his animosity towards Picard. Ruhalter and Picard were both fencing afficionado and would often spar together in the Stargazer's gymnasium.

In 2333, the Stargazer was ordered to investigate the threat of a Nuyyad attack from beyond the galactic barrier. After crossing the barrier, the Stargazer was attacked and crippled by the Nuyyad, which left Captain Ruhlater dead, and Leach in a coma. Picard assumed command and got the Stargazer to safety at Magnia colony.

Although Leach had presumed that Captain Ruhalter had been oblivious to his feelings of displacement, before his death Ruhalter had a private meeting with Picard to discuss his true feelings about Leach’s inability to fit into the Stargazer’s command structure and his wish to transfer him to a position in Starfleet where his skills and abilities were best utilized. Captain Ruhalter confirmed that upon Commander Leach’s transfer he would like nothing better then Picard to assume the role of his new first officer, which Picard reservedly accepted.

Following the successful completion of the mission, Admiral Mehdi promoted Picard to captain and placed him in permanent command of the Stargazer. Although there was no documenation of Captain Ruhalter’s wish to transfer Leach, Admiral Mehdi conveyed the same feelings about him, and advised that once he recovered from his coma he would be transferred to a position within Starfleet that would benefit from his particular skills. Leach’s activities post-transfer from the USS Stargazer are unknown. (TNG novel: The Valiant)

USS Stargazer personnel
USS Stargazer (NCC-2893)	Ang • G. Asmund • I. Asmund • G. Ben Zoma • E. Bender • J. Caber • T. Cadwallader • A. Carriello • J. Crusher • Durand • S. Grace • C. Greyhorse • Jiterica • P. Joseph • N. Kastiigan • Ki'hiut • S. Leach • Lisuni • I. Maisel • Merritt • Morgen • A. Nikolas • Obal • C. Paris • J.L. Picard • B. Refsland • D. Ruhalter • Satran • Schuster • P. Simenon • Stroman • Suranyi • T'Moni • D. Ulelo • Urajel • J. Valderrama • Vigo • Werber • E. Wu • Yojaleya
USS Stargazer (NCC-2893-A)	Hendry • Rackham