Puerto Rico's Justice Secretary Wanda Vázquez became the third person in a week to occupy the post of governor of the U.S. territory.

Vázquez was sworn in late Wednesday afternoon, hours after the island's Supreme Court unanimously ruled that part of the law used by embattled Gov. Ricardo Rosselló to name Pedro Pierluisi as his successor was unconstitutional.

The Supreme Court decision came after Senate President Thomas Rivera Schatz filed a lawsuit Monday, asking courts to immediately remove Pierluisi from his post based on the fact that the events didn't follow the constitution.

Vázquez, who was appointed as Justice Secretary in 2017, is seen as loyal to Rosselló and protesters gathered in front of the governor's mansion shortly after she was sworn in. The hashtag #WandaRenuncia (#WandaResign) was already trending on Twitter.

"I arrive at this position by constitutional provision and by opinion of law, but with the greatest respect and determination to serve my people and to push Puerto Rico forward," said Vázquez in a statement after being sworn at the Puerto Rico Supreme Court in San Juan. "It is with great humility and commitment that I assume the position to direct the destinies of our country, with responsibility and delivery."

Late Wednesday night, Vázquez tried to appease critics during her first televised address as governor, saying she hopes to foster “a conciliatory and inclusive dialogue” and work towards seeking “consensus on everything we do not agree on” even though she was not elected by the people of Puerto Rico.

She also spoke about her plans to meet with leaders across the board, from lawmakers to religious and community leaders, in upcoming days.

Vázquez is a member of the political party in power, which supports statehood for Puerto Rico, as well as Rosselló, Pierluisi and Rivera Schatz.

Rosselló had chosen Pierluisi to fill the secretary of state vacancy left by Luis G. Rivera Marín, who resigned last month over his involvement in the chat scandal that led to Rosselló’s resignation after weeks of historic protests.

According to Puerto Rico’s Constitution, the island's secretary of state is next in line if the governor position is vacant. But at the core of the legal dispute was the question of whether Pierluisi was a legitimate secretary of state in a position to become Rosselló's rightful successor.

"It's unconstitutional to allow a Secretary of State to become Governor without having been confirmed by both legislative chambers," the Supreme Court said in a press release.

While Pierluisi had been confirmed as secretary of state by Puerto Rico's House of Representatives an hour before he took his oath as governor Friday, the island's Senate had never taken a vote on the nomination.

Senate president Rivera Schatz postponed the vote to this week, after Rosselló's resignation became official, but that vote never happened.

Instead, Schatz went to court, arguing that Pierluisi did not “occupy the position of secretary of state in property” because he wasn't confirmed by both Houses.

Pierluisi, a former resident commissioner and an attorney, argued that wasn't the only way that the secretary of state could be ratified.

In his defense, Pierluisi cited the law of succession of 2005, which incorporated a recommendation made by the island's Department of Justice that waives a secretary of state’s confirmation requirement in case of an emergency.

Vázquez is both Puerto Rico's second female governor and second unelected governor in seven decades.

She has voiced her lack of interest in occupying the position and she has faced opposition from Puerto Ricans who see her as part of Rosselló's inner circle. Last week, the hashtag #WandaRenuncia (or "Wanda, resign") started trending after Rosselló hinted in his resignation address that she would most probably succeed him, since at the time he hadn't named Pierluisi as secretary of state.

Vázquez initially described the leaked chats that ousted Rosselló as "incorrect" but not illegal. She later announced that she would recuse herself from any investigation because she was mentioned in the chats.

Minutes before Vázquez was sworn in, Pierluisi issued a statement: "I wish the Honorable Wanda Vázquez Garced the greatest success as Governor of Puerto Rico. I will always be in the best disposition to advance any initiative that seeks to improve the quality of life of our people and to encourage the Federal Government to fulfill its responsibility to provide the support that Puerto Rico needs for its recovery and reconstruction."

Local news outlets reported last month that the Office of Government Ethics will investigate conversations between Vázquez and a former top administration official over her decision not to investigate allegations about the mishandling of much-needed post-hurricane provisions.

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