Five months after he was declared not guilty, Avinash Treebhoowoon has lodged a civil suit against police and the government seeking damages of 75m Mauritian rupees (€1.8m).
The lawsuit targets the Indian Ocean island's Major Crime Investigation Team, police commissioner and the government.
In the action, Mr Treebhoowoon alleged another hotel worker, Raj Theekoy, who was the prosecution's star witness, conspired with police officers and lied in court so as to implicate him in the murder of Ms McAreavey.
Ms McAreavey, daughter of Tyrone Gaelic football manager Mickey Harte, was strangled in her hotel room while on honeymoon with her husband John in January 2011.
Mr Treebhoowoon, a hotel room cleaner, and Sandip Moneea, his supervisor, were both quickly arrested and charged with her murder.
However, Mr Treebhoowoon claimed a confession he made was beaten out of him by police.
A jury unanimously cleared both defendants.
A new investigation into the circumstances surrounding Michaela's murder – conducted by a different team of officers – was launched after they were acquitted. To date, no other suspects have been charged.
One man, former hotel security guard Dassen Narayanen, still faces charges of conspiracy to commit larceny, in relation to alleged theft from the McAreavey's room.