Merle's first ever appearance is in the 2005 version of Ciem 2, working with internal affairs. His role is quite limited here, alleging that Donte is a corrupt police chief and insinuating that he and Candi are sleeping together. He later becomes police chief after Donte resigns. He tries to give Arfaas an edge in conquering Dirbine by Ciem 3, but ultimately fails and dies.
See also: Ciem (webcomic)
So far, this is the most-developed version of Merle in existence. Merle is the police chief of Dirbine, and is secretly an Arfaas sympathizer. He and a small number of police use office politics to bring about the resignation or firing of all police not in league with Arfaas somehow, then use their new disposition to turn the town into a police state with Arfaas as supreme dictator. A handful of freedom fighters remain and resist; but live in fear. Merle grows increasingly unhinged in his efforts to help Arfaas out, especially as rumors about Ciem become more numerous. He is also portrayed as being monstrously cruel, even whipping a defenseless Donte in prison to get information out of him.
He is last seen raving like a lunatic in the streets with other Arfaas loyalists, fighting in vain to keep Ploribus Philippine and company out of Dirbine. His body is quickly set on fire amidst all the murder and mayhem, with nobody missing him once he's reduced to ash.
See also: Ciem: Vigilante Centipede
Merle remains a police chief in this version, though he is slightly younger than previous incarnations. He meets Arfaas in different locations and will die differently than last time. However, his profile has yet to be fully fleshed out.
Merle has always been assertive, aggressive, and fairly mean-spirited. As for his fanaticism in favor of Arfaas, that developed over time. He has had very little development over time as the story has progressed from one version to the next, other than to become increasingly an insider in Arfaas' plans and increasingly active in pushing for taking over Evansville. His role is vital, even though he has become flatter as a character overall.
Merle's first appearance portrayed him as being mean to Candi, but not particularly evil. He was there merely to show that Donte was not entirely above reproach when it came to how he treated others under him. However, this limited role only made sense in the greater context of Gerosha Prime and how that universe functioned. By Classic Gerosha, the world no longer operated on those principles. He was changed in Ciem to a fanatical follower of Arfaas' who practically worships the ground Arfaas walks on. Even in Vigilante Centipede, he remains crucial towards being an inside man to helping Arfaas achieve his goals. However, his role has become more active.
Merle was first generated in The Sims 2 using the Tombstone of Life and Death. While he was not originally known as Merle, he was given that name so that he could be named after Merle Haggard. He was an elder officer who could question Donte's judgment and credentials in letting Candi rise in ranks so quickly. Subsequent uses of the character have been pre-defined and deliberate, however. His overall persona is inspired by a similar officer, who was defeated in a shootout with Mitch Brandel during The Battle for Gerosha.