Lula's third-term efforts to fill the STF vacancy created by Justice Luís Roberto Barroso's October 2025 retirement center on Senate confirmation dynamics and pre-electoral positioning ahead of Brazil's October 2026 general vote. His initial November 2025 nomination of Attorney General Jorge Messias was formally transmitted in early April 2026 but rejected 42-34 on April 29—the first such defeat in over 130 years—amid opposition concerns over judicial power and Senate influence. Lula has publicly reaffirmed plans to resubmit Messias or another candidate, potentially a woman, with Senate rules permitting a new indication outside the same legislative session. Key variables include coalition negotiations with Senate President Davi Alcolumbre, vote thresholds requiring at least 41 approvals, and timing pressures before the campaign intensifies. These factors shape trader assessments of announcement likelihood by any near-term deadline.