The answer is: Omri's

Micah 6:16 - The statutes of Omri, (see 1 Kings 16:25 But Omri wrought evil in the eyes of the LORD, and did worse than all that were before him). The verse also talks of the practices of Ahab. (1 Kings 16:30 And Ahab the son of Omri did evil in the sight of the LORD above all that were before him). These were bad kings, who brought nothing but evil to the nation of Israel. The people of Judah were following after the ways of these two evil kings.

In Micah’s time, the choice of whom to follow represented the moral compass of the people. The reference to Omri and Ahab serves as a stark reminder of how leadership echoes through history—setting a standard that communities, perhaps unwittingly, adopt. Captivated by power, wealth, or popularity, kings like Omri and Ahab led Israel into deeper disobedience, prompting Micah to urge a return to righteousness. Their reigns spotlight not just the dynamics of ancient politics but also the hazards of failing to question authority.

One interesting trivia note: Omri is more than just a notorious figure in the Bible; he's also mentioned in Assyrian texts! His military prowess as a leader secured Israel’s standing among its neighbors, but at a grave spiritual cost. Stories like this underscore how personal and societal crises often stem from a good-looking exterior that hides moral decay. The prophets, including Micah, emerged as voices against complacency, calling out sacrificial rituals that had cheapened in sincerity—a cry for authenticity that reverberates even today.

Moreover, it's fascinating to see the role of prophets like Micah—they’re not merely speaking against lonely kings; they are champions of conscientious living among the populace. Without the guidance back to a heartfelt devotion—a practice lost in the robust rituals modeled after corrupt rulers—peace was become a distant memory for Micah’s audience. Surely, anyone following in the ways of Ahab and Omri would find themselves struggling for genuine joy and fulfillment.