The head of Sussex Police has ordered officers to respect the public in the wake of controversy over the G20 protests in London.

Chief Constable Martin Richards’s comments come as the force prepares for a test of its own public order policing when a planned demonstration takes place on May Day against the EDO MBM Technology arms factory in Brighton.

More than a thousand people are expected to turn up on Bank Holiday Monday and organisers have refused to reveal their plans as police prepare for a repeat of disorder at two protests last year.

Protests in central London earlier this month have led to claims of Metropolitan Police brutality.

Amateur videos and photographs appeared to show unprovoked attacks on demonstrators.

Every officer and member of staff in Sussex Police has now received an email from Mr Richards warning them to behave.

He said: “People’s confidence in policing has been shaken by things they have seen on their TVs and read in their newspapers, most of it relating to the policing of the G20 protests in London.

“It is time, I suggest, for a re-statement of our values, loud and clear.

“They include integrity, fairness, compassion, courage, openness, generosity of spirit - and humility.”

He said officers should see themselves as public servants and reminded them of the force’s watchwords, Serving Sussex.

He said: “In the debate that is gathering about whether the police see themselves as the servants or masters of the people, let there be no doubt where I stand.

“As I have said repeatedly, though in a different context, Serving Sussex is neither a slogan nor a catchphrase – it’s what we do.”

The protest against weapons components factory EDO MBM Technology in Home Farm Road, Moulsecoomb, is planned for midday on May 4.

The location of the “mass street party” is not being released until just before it begins.

Hundreds of demonstrators clashed with police at a Carnival Against The Arms Trade at the Home Farm Road plant in June last year.

A further protest in October was also marred by confrontation. Ten people were arrested and the police estimated the cost of the operation at £50,000.

Smash EDO issued a statement this week in response to an article in The Argus in which police said the cost and the chance of disorder at the May Day event are much greater because they have been unable to negotiate with the organisers.

It said: “In a climate where our civil liberties are being rapidly eroded why should we grant more rights to the police in order for them to control us?“ Ben Duncan, a Green councillor for Brighton and Hove City Council’s Queen’s Park ward who is a member of Sussex Police Authority, said he was encouraged by the comments of Mr Richards.

He said: “I hope whatever happens on May 4 we do not see a repeat of what we saw at the G20. I hope no demonstrator or police officer is made to feel threatened or suffer violence or intimidation.“