"I make a renewed commitment to work hard for my constituents, for the people that I represent, and to ensure that we do right by them. I am headed to Albany to do the people's business," Monserrate said.
He was convicted of misdemeanor assault after a domestic dispute with his live-in girlfriend, Karla Giraldo.
Monserrate, in a tearful statement to Justice William Erlbaum, said he took full responsibility for his actions and looked forward to resuming his life with Giraldo.
"I am so sorry for the harm Karla Giraldo endured and suffered," he said. "I will not let her down, I will not let the court down, and I will not let my community down."
During the trial, the prosecution claimed Giraldo was attacked with a broken drinking glass, but the state senator insisted it was an accident and she backed-him up.
With no independent eyewitnesses, the court dismissed the allegations, Monserrate was convicted for dragging her through the hallway like a ragdoll in the moments that followed. That was all caught on tape.
Victims usually demand the maximum sentence, but Giraldo begged the judge for leniency.
"I am here because I have always said this was an accident," she said. "I want to be with him."
She urged the judge to lift the restraining order against Monserrate.
"He does not dominate me. He does not have control over my life," she said. "This was not a case of domestic violence."
Giraldo rushed from the courthouse and said nothing to reporters after the judge refused to lift the order.
"He doesn't get a break. He doesn't get a handout. He gets what any other person gets in this situation," said Judge Erlbaum.
Monserrate and Giraldo have been under a court order not to see each other since shortly after their violent encounter was caught on video last December. She sought to have the order lifted and said Friday that the two planned to marry, but the judge kept the protection order in place.
Some lawmakers and other public officials have called for Monserrate's resignation.
The Senate's Special Committee of Inquiry will hold two meetings in the next 10 days to review the matter. Two members appeared in court to ask the judge for grand jury testimony and were granted access to Giraldo's statements.
After completing its investigations, the panel will report to the Senate with its recommendations, said James Freedland, a spokesman for Sen. Eric Schneiderman, who heads the committee.
Erlbaum said the "the Legislature has in its membership a flawed human being," but cautioned senators not to rush to remove Monserrate from the chamber.