The teacher acquitted of a racially aggravated public order offence after she held a placard depicting Rishi Sunak and Suella Braverman as coconuts at a pro-Palestine protest has called on the police watchdog to investigate the Metropolitan police over its handling of the case.

Marieha Hussain, who was found not guilty at Westminster magistrates court earlier this month, claims the Met and the Crown Prosecution Service (CPS) pursued a politicised case against her without justification after she attended the march in November last year.

“It has damaged my reputation and lost me my career. They must answer for the harm they have caused not just to me but equally the right to peaceful protest,” she said.

Hussain’s solicitor at Birnberg Pierce submitted complaints to the Independent Office for Police Conduct (IOPC) and CPS last week about the handling of the case, which they claim went forward “despite unsound evidence and in the face of clear contrary legal principles”.

The CPS said it had received the complaint and would be carefully considering its content and responding to it.

A statement by Hussain’s solicitor, Gareth Pierce, shared with the Guardian, read: “The Metropolitan police and the CPS failed inexcusably in their respective responsibilities, seriously undermined the exercise of free speech and exposed Hussain to irreparable harm.”

Pierce was particularly critical of the Met for responding to a picture of Hussain holding the placard, which was posted by the rightwing blog Harry’s Place on X in November last year, saying it was “actively looking” for the woman in the picture.

The statement reads: “The Metropolitan police six hours later lent its full authority to a fresh, dangerously wrong formulation, by itself disseminating the ‘Harry’s Place’ photograph with the assertion that the person depicted was wanted in relation to an investigation of a hate crime, without regard to any duty of safeguarding towards a young woman very clearly offering no threat.”

During Hussain’s trial, the prosecution claimed “coconut” was a well-known racial slur. It has “a very clear meaning, you may be brown on the outside but you are white on the inside,” said the prosecutor, Jonathan Bryan. “In other words, you’re a ‘race traitor’, you’re less brown or black than you should be.”

The district judge Vanessa Lloyd, however, ruled in favour of Hussain. She said the placard was “part of the genre of political satire” and that the prosecution had “not proved to a criminal standard that it was abusive”.

In her first full interview since being acquitted, Hussain described the immense impact that the media attention and trial had had on her life, which led her to lose her job and move home and exposed her to a barrage of online abuse.

A spokesperson for the CPS said: “Our prosecutors reviewed this case carefully and concluded there was enough evidence for it to be presented to a court. The defendant was found not guilty and we respect the judge’s decision.”

The Met and the IOPC have been approached for comment.