Emmet is a member of the Seville Boulevard Families, an ally of the Grove Street Families. Emmet runs a small-time gun dealership in Willowfield, Los Santos although he is unable to compete with Ammu-Nation, who own a store opposite. Emmet, who has been providing guns for over thirty years, supplies not only the Seville Boulevard Families but the Temple Drive Families and Grove Street Families also.
Emmet is known to the Johnson Family (in particular Carl and Sweet) along with Big Smoke and Ryder. However, they stopped buying guns from Emmet as his stock was out of date. Emmet, during the mission Nines and AKs, mistakes Carl for his deceased younger brother Brian. Emmet also appears to have known Beverly Johnson (Carl's mother) and says that he is sorry about her death and that he knows that she would be proud of him (Carl).
Emmet provides basic target practice for Carl and Big Smoke with old pistols he had in storage. The targets being glass beer bottles and an old car. However, Emmet reminds them to not say where they got the guns from, suggesting he does not have a licence to sell guns: "But remember this, you didn't get 'em from me". Emmet leaves a pistol in the yard he runs his business from for Carl to pick up, which is free for Carl.