The problem is that here in Brazil crimes committed by military are judged by a special military court, and that usually means being judged by peers, friends or acquaintances. Also his terrorist plan was a protest for better salaries for officers, so he wasn’t really seen as an enemy to our military force, just a passionate crazy dude. They basically let him go with a slap on the wrist, and he entered politics sometime after that.

In October 1987, Bolsonaro faced a new accusation. Veja reported that, with an Army colleague, he had plans to plant bombs in military units in Rio de Janeiro. After Bolsonaro called the allegation "a fantasy", the magazine published, in its next issue, sketches in which the plan was detailed. The drawings had allegedly been made by Bolsonaro. Official records unearthed by the newspaper O Estado de S. Paulo in 2018 detailed the case.[31] After an investigation by an administrative military bureau named Justification Board, Bolsonaro was unanimously considered guilty. According to this board, Bolsonaro had a "serious personality deviation and a professional deformation", "lack of moral courage to leave the Army" and "lied throughout the process" when denying frequent contacts with Veja. The Supreme Military Court then analyzed the case. The general in charge of reporting the case voted to acquit Bolsonaro, arguing that he had already been penalized for the initial Veja article, that there was no testimonial evidence of his plans to plant bombs, and that there were "deep contradictions in the four graphological exams", two of which failed to conclude that Bolsonaro was the author of the sketches. Bolsonaro was acquitted by the majority of the court (9 v 4 votes). In December 1988, just after this ruling, he left the Army to begin his political career. He served in the military for 15 years, reaching the rank of captain.

https://en.m.wikipedia.org/wiki/Jair_Bolsonaro