Chaiken was an efficiency auditor working for the Federation Auditor General during the 2270s.
In 2275, Chaiken was assigned to a team that audited the USS Enterprise. Due to resistance from the senior staff, many areas of the ship were off limits to the auditors, but Chaiken and Roberta Gendron gained access to sickbay, but they were forced to take notes with a manual pen as Doctor McCoy had banned electronic devices. Later in the voyage, Chaiken was killed by the Orion spy who had assumed the identity of Lindsey Purviance. (TOS novel: Death Count)