Larry Butz grew up alongside Phoenix Wright and Miles Edgeworth, knowing them since elementary school. A fourth-grade classroom trial cemented his complex dynamic with them; he joined Edgeworth in defending Wright, falsely accused of stealing lunch money, while secretly being the actual thief. This established Butz's lifelong pattern of dodging responsibility yet displaying fierce loyalty to his friends. He later described himself as a "bona-fide junior high school graduate," confirming his lack of higher education.

Butz landed as Wright's first client when accused of murdering his girlfriend, Cindy Stone. Wright secured his acquittal by exposing Frank Sahwit as the killer, simultaneously shattering Butz's idealized view of Stone through revelations of her secret relationships. Despite Wright's success, Butz neglected to pay his legal fees. His life remained characterized by instability: he cycled through at least five jobs and nine girlfriends within three years, relationships often ending abruptly.

While working as a Gourd Lake hot dog vendor, Butz witnessed crucial details surrounding Robert Hammond's murder on Christmas Eve, retrieving an inflatable Steel Samurai balloon. His testimony about hearing a gunshot near midnight became vital evidence in Wright's defense of Edgeworth. Following the trial, Butz confessed and repaid Edgeworth for the stolen childhood lunch money.

Later, a part-time job at KB Security under Wendy Oldbag placed him at the scene of Kane Bullard's murder. His negligence—leaving his post after an argument and ignoring the CEO's panic buzzer—contributed to the crime. During the investigation with Wright and Maya Fey, Butz demonstrated a contradictory pattern of distrusting women while actively flirting. He provided evidence like Ron DeLite's wallet but avoided personal accountability.

Seeking reinvention, Butz adopted the pen name "Laurice Deauxnim," claiming apprenticeship to children's author Elise Deauxnim and expressing a dislike for his unreliable past self to become a picture book artist. Yet familiar behaviors resurfaced: he fell for Iris, a Hazakura Temple nun, and anonymously sent her a "blackmail" letter demanding a meeting, inadvertently distressing her due to unrelated secrets.

On the night of Elise Deauxnim's murder, Butz witnessed Dusky Bridge ablaze after lightning and reported seeing a hooded figure flying overhead. His sketch of the scene, initially baffling due to its poor quality, was later correctly interpreted upside-down, revealing the figure swinging *under* the bridge—key evidence aiding the investigation. He contacted Edgeworth for help after Wright fell into Eagle River during the bridge collapse, exaggerating Wright's condition.

Butz reappeared years later during the "Turnabout Time Traveler" incident, insisting on marrying a woman already engaged and suspected of murder. His core personality endured: talkative, emotionally volatile, prone to lying or withholding embarrassing information. Despite his flaws, he consistently supported Wright and Edgeworth in crises, like expressing deep concern for Maya Fey's safety during her kidnapping.

Artistically, Butz demonstrated skill in crafting functional "Thinker" clocks and detailed portraits, though others frequently dismissed his work. His acting ability shone when he convincingly portrayed the Steel Samurai, impressing even Edgeworth. The schoolyard adage "When something smells, it's usually the Butz" aptly summarized his knack for inadvertent involvement in trouble. Brief periods of motivation for self-improvement emerged, yet his foundational traits of insecurity and avoidance persisted.