Simon was scheduled to have a hearing Tuesday, but it was canceled and all potential charges against Simon in the death of his 25-year-old cousin, Michael Castillo Almonte, were dropped, according to Simon's representatives.
Orioles director of player development John Stockstill, who has been the point man for the organization during this ordeal, spoke to Simon Tuesday afternoon and said: "He was acquitted of all wrongdoing and is very relieved. He is looking forward to focusing 100 percent on his baseball career."
Simon's lawyer, Dinora Diloné, told the Associated Press that prosecution witnesses said they did not see Simon fire a shot and ballistic tests determined that the bullet extracted from Almonte's body did not match Simon's gun.
"With this decision, Alfredo is acquitted, although the prosecutor has the possibility of appeal," Diloné told the AP. "But it is unlikely [because] there was no evidence to show that he was involved."
Simon told the AP on Tuesday: "I am grateful that justice was done and everything went well. Now I just want to work in baseball and [with] a clear mind because I think it'll be better. Now we have to work hard, just ask the [youth] to be careful in the streets."
Victor Mueses, the prosecutor in the case, could not be reached for comment.
The decision could end a yearlong saga in which Simon spent two months in a Dominican prison but was never charged with a crime. The right-hander missed all of spring training in Sarasota, Fla., started the season pitching for Double-A Bowie while on baseball's restricted list, and finally returned to the Orioles' bullpen in late May.
Simon, 30, moved to the starting rotation in July. He finished the season with a 4.90 ERA and a 4-9 record in 23 games (16 starts), striking out 83 batters and walking 40.
All the while, the uncertainty surrounding Simon's legal issues hung over his head. On two occasions before Tuesday, hearings were scheduled — including one in late July, when Simon left the team briefly between starts to fly back to the Dominican Republic — but witnesses did not show.
"The whole year, he did a good job of pitching through this process," Stockstill said. "It's incredible, some of the things he did, given the burden on him."
Simon maintained his innocence after he rejoined the team following the first postponement.
"They don't have any proof. ... They don't have any proof about the ballistics [on his gun]," Simon said July 19.
"I have never been in trouble like that before. I haven't been charged. If I had been charged, I'd be in jail. But they can't because they don't have enough proof. Sometimes they try to get money from players or whatever, so we'll just wait and see what happens."
Had he been found guilty of manslaughter, Simon would have faced up to two years in prison.
The pitcher's role with the Orioles heading into 2012 is unclear.
Simon had said he was looking at his September starts as auditions for next season, and Orioles manager Buck Showalter said that despite uneven performances down the stretch, Simon — who has made 19 career big league starts — was presenting himself as an option for the rotation.