CHICAGO (CBS) — Speaking publicly for the first time since his ouster as a Chicago Public Schools principal, frequent Emanuel administration critic Troy LaRaviere blasted the mayor and school board, accusing them of orchestrating his removal because he was seeking the top post at a school administrators’ group.

LaRaviere was removed as principal of Blaine Elementary School last month, accused of misconduct and ignoring warnings from his bosses.

The Chicago Public Schools have not provided details of the allegations against him, but LaRaviere said he was accused of insubordination, dereliction of duty, and ethics violations tied to his public support for presidential candidate Bernie Sanders and Jesus “Chuy” Garcia, who ran against Emanuel last year, He called the to fire him an act of political retribution.

“Today, I’m here to respond to the politically motivated charges that they’ve assembled as a false justification for that removal,” LaRaviere said at a press conference at a Lakeview restaurant, surrounded by supporters.

LaRaivere has often criticized Mayor Rahm Emanuel, and his administration’s handling of the city’s school system, and held nothing back on Thursday.

“Their education policies have been ideologically driven, clumsy, and scientifically baseless. I’ve talked with so many principals who are deeply troubled by the obstacles this administration puts in their way; underfunding, a flawed school ratings system, a lack of support for schools that serve the most vulnerable children, and a lack of respect for their time, a culture of fear and intimidation, and burdensome compliance-driven paperwork. The list goes on,” he said. “Under this administration, teaching, learning, and leading are far more difficult than they have to be.”

He has frequently accused the Emanuel administration of engaging in wasteful spending and disastrous borrowing, while steering district money to banks that profit off CPS debt.

“This administration is focused on creating financial relationships that ensure rich donors profit from our students’ losses. It is inherently corrupt, and corruption breeds incompetence,” he said.

LaRaviere said he believes his firing is linked to the fact that he was nominated for election as president of the Chicago Principals and Administrators Association.

“When I was the lone voice, the administration tolerated it, but when faced with the prospect of an organized group of education leaders speaking as one on behalf of our students, they moved with haste and reckless abandon to prevent that from happening,” he said.

LaRaviere said Blaine is one of only four schools that has consistently and substantially raised student achievement for several years, according to the standards used by the Emanuel administration.

He also accused the district of wasting $2,000 by having the locks changed at Blaine after he was removed from his post.

“You could have just got my keys. You just spent $2,000 changing locks. Why did you do that? It’s a psychological tool,” he said. “You remove me from my school, and then you go around and change all the locks, and give different keys to people to give the sense that this is someone who’s unsafe; that he must have done something.”

CPS officials responded to LaRaviere in a brief statement:

“Mr. LaRaviere has made public the charges that CPS provided to him on April 25, 2016. Those charges set forth the bases for CPS’ decision to remove him as a principal. An independent arbitrator will hear evidence concerning those charges and make a recommendation concerning Mr. LaRaviere’s employment.”