Mr Syvret has accused the report's author of unlawfully intimidating him.Senator Stuart Syvret bullied and harassed States employees, an independent UK investigator has said.
Employment judge Christopher Chapman said he was visibly taken aback by the abusiveness of some of Mr Syvret's postings on his internet blog.
The States Employment Board, which ordered the report, should have done more to stop his behaviour, Mr Chapman concluded.
Mr Syvret refused to comment to BBC Jersey about the report's findings.
The independent report was commissioned in May following several complaints to the board about the blog.
In it Mr Syvret had used terms like dishonest, incompetent and criminal to describe civil servants.
"What he is not allowed to do is to use the language that he does and to keep making allegations unsubstantiated by evidence"
Christopher Chapman
The language went beyond the legitimate expression of concern by a politician, and into a misuse of power, said Mr Chapman.
People named on the blog have had trouble sleeping and maintaining normal family life and their children had been bullied as a result of allegations made, the report said.
But the employment board was also at fault for not doing more to stop the allegations, it added.
Mr Chapman said the blog had raised some valid points.
"I made it clear in my report that a States senator he's entitled, if not obliged, to raise issues of public concern.
"He has done that and there are a number of issues in which he writes in very moderate language.
"But what he is not allowed to do is to use the language that he does and to keep making allegations unsubstantiated by evidence; that goes beyond free speech."
Wanted by police
Syvret should 'put up or shut up'
Mr Syvret refused to meet Mr Chapman as part of the investigation, but did email a response which is contained in the report.
In it he claimed that Mr Chapman was intimidating and threatening him.
He wrote: "You think - do you - that a UK bureaucrat such as yourself has the right to interfere with the democratic will of the 15,000 people who voted for me, by being a party to an unlawful act of harassment, intimidation - and "bullying" - against me?"
The report also made six recommendations, which Jersey's Chief Minister said the employment board would adopt. Senator Terry Le Sueur said he had asked the body in charge of standards of politicians' behaviour to consider taking action against Mr Syvret.
Mr Syvret is wanted by island police for failing to appear in court to face motoring and data protection charges.
Liberal Democrat MP John Hemming said Mr Syvret was staying at his London flat while seeking asylum in the UK on legal grounds.
The senator said he left Jersey as he felt he would not get a fair trial.
Politician 'bullies and harasses'