The Solo-Niathal coup d'état, an event that transpired in 40 ABY amidst the Second Galactic Civil War, involved Jacen Solo overthrowing Cal Omas, the then-Chief of State. This power grab resulted in Jacen Solo and Cha Niathal jointly assuming the role of Chiefs of State for the Galactic Alliance.
With the conflict raging, Omas found himself with limited options for retaliation. However, an opening presented itself when Dur Gejjen, the leader of the Corellian government, reached out to him to explore peace negotiations. Omas, during a meeting with Gejjen on Vulpter, proposed that Jacen Solo, the commander of the Galactic Alliance Guard, and Cha Niathal, the Supreme Commander of the Galactic Alliance Defense Force, be removed from their positions. In exchange, Corellia would rejoin the Alliance, and the war would end. Gejjen agreed, but shortly after departing the meeting, he was fatally shot in the head by Ben Skywalker, a sniper from the GAG. Omas managed to return to Coruscant safely, but he was now isolated and without allies.
Upon discovering these events, Solo concluded that Omas was no longer suitable to lead. He began to delve into galactic law and started campaigning for greater authority, which the Senate ultimately granted. Eventually, he acquired the necessary power to remove Omas from office. Solo also forged an understanding with Niathal.
Exploiting a legal technicality, Jacen Solo, accompanied by a GAG escort consisting of Sergeant Wirut and Trooper Limm, entered Omas' residence at Republica House. Solo placed Omas under arrest, who reacted with cold detachment in front of the soldiers. However, once they were alone, he launched a verbal attack on Solo, denouncing him as a "power-crazed…little jerk." The official justification for the arrest was Omas's secret negotiations with Dur Gejjen; however, the Justice Department did not formally charge him until a significant period after his detention.
Cha Niathal, stepping in as the acting Chief of State, declared that both she and Solo would serve as joint Chiefs of State. They asserted that their assumption of power was lawful and temporary, promising swift elections once the war concluded. Furthermore, they sealed off the Chief of State's office, stating that only democratically elected officials could occupy it.
Initially, the move caused shock among many senators and citizens. However, Niathal's address to the Senate and Jacen Solo's interaction with protesters largely diffused any major opposition. The general population seemed to accept the transition with minimal resistance.
While Admiral Niathal genuinely believed that the coup was a temporary measure for the duration of the war, Jacen Solo secretly began to formulate his plans to eventually rule the entire galaxy as a Sith Lord. As Solo's actions became increasingly questionable, Niathal grew increasingly concerned about her co-chief of state, especially after he had – without her knowledge – transformed into the Sith Lord Darth Caedus. Upon learning that Caedus had murdered Lieutenant Patra Tebut in a fit of rage, she wanted to relieve him of his duties and arrest him for his crimes, but she knew that the [Galactic Alliance Guard](/article/galactic_alliance_guard] would not support her.
Some months later, Admiral Niathal and Darth Caedus attacked Fondor in an effort to subdue a critical Confederation world. When Darth Caedus ignored an order to stand down after the Fondorians had surrendered, Niathal attempted to remove him from command. The majority of the fleet remained loyal to Darth Caedus, who promptly retreated to Coruscant. Niathal remained on Fondor, establishing an Alliance-in-exile on that planet.
It is speculated that the joint-Chiefs system may have served as the inspiration for the later Triumvirate.