Watch Victoria Davies' report
The Mayor of Bristol says Avon and Somerset Police have shown they are capable of managing protests "well and with sensitivity".
His comments follow the third Kill The Bill protest within the space of a week on 26 March which turned violent.
The Labour mayor called the actions of some protesters "politically illiterate and strategically inept", suggesting their actions could make the bill more likely to pass.
He added there were a number of people in attendance "merely to cause conflict".
Mr Rees comments follow those made by Prime Minister Boris Johnson condemning the "disgraceful attacks" on police officers.
However, protesters in Bristol responded to the criticism saying the police were heavy-handed in their response.
Protestor Saranya Phambirajah says the event turned violent one officers started to charge at the crowd.
Marvin Rees statement in Full
"The violence on our streets is unwelcome. Of particular concern are the number of people travelling into our city to protest or to cause conflict. You can protest in your own town or village, without travelling to ours.
"The question those engaging in the action should be asking is: is what I am doing advancing the cause I claim to be campaigning for? Many people protested peacefully but there are a number who refuse to go home and others who are here merely to cause conflict: the Bill itself is not their cause, it is their opportunity.
"If the protests are meant to reduce the likelihood of the Bill, then the actions of some of these protestors are politically illiterate and strategically inept. The actions make the Bill more likely and protesting in Labour-led Bristol does not put any pressure on the Conservative MPs who will be required for the Bill to pass.
"Avon and Somerset Police in Bristol have shown they are capable of managing protests well and with sensitivity and have developed a strong culture of working with our communities. The numbers of people coming to Bristol mean more police have had to be brought in from neighbouring constabularies.
"This makes it more difficult to drive the culture we have been building over recent years. Our local leadership have a difficult job and they have the highest standards to maintain.
"We know they will review some of the incidents that occurred last night and ensure those standards are upheld.
"Everyone has a responsibility for their own actions - be honest about your role and your intentions. And any activism has a responsibility to get its strategy right, especially when it is the most vulnerable who will pay the price for failure. Any protests must be thoughtful, meaningful, peaceful and accountable."
Why are people protesting?
People have been demonstrating against a proposed Police, Crime, Sentencing and Courts Bill, which would give police increased power to stop protests.
The Bill also makes a special new law to protect monuments and statues, in the wake of the toppling of the statue of Edward Colston, with the crime of damaging them punishable by up to ten years in prison.
Under new government proposals trespass would become a criminal offence - rather than being a civil matter - in order to tackle unauthorised encampments, giving police the power to seize vehicles and arrest people who refuse to move.
Those breaking the new law on trespass could be fined up to £2,500 and could face a prison sentence of up to three months, but concerns have been raised by both academics and organisations that the new law will disproportionately affect travellers and more widely those living on roadside camps.