Liana and Elena Bobolas were arrested outside their home in July 2015 after allegedly breaching a court order not to go within 10 metres of council workers cleaning up their property and of machinery such as trucks.

The sisters, who represented themselves, challenged the charges on numerous grounds including by claiming police were trespassing and used unreasonable force and violence.

But in Sydney's Downing Centre Local Court on Tuesday, magistrate Jacqueline Trad found proven three obstruction offences against Liana Bobolas and one against Elena Bobolas.

Video footage taken by a council contractor "speaks for itself" and was clearly relevant as it captured the alleged obstruction as well as events which the sisters said justified their actions, she said.

Rather than showing police brutality, officers were seen to be "gentle, calm and patient" while the sisters were combative and argumentative.

The women were not arrested until after they were given several warnings, she said.

Elena Bobolas, who was accompanied by her mother, told the magistrate her sister was not present in court as she was unwell.

Ms Trad said she had seen the sister as she came into the complex on Tuesday but accepted she may have become unwell.

She asked Elena Bobolas if she had any sentence submissions but was told: "I didn't do anything. I am not guilty."

"There is no recognition of wrongdoing by Ms Bobolas and clearly no contrition or remorse," the magistrate said.

But the court needed to exercise some compassion in the case as there was obviously an "element of this which is very concerning".

"There must be other factors at play," the magistrate said

"There are other issues in relation to the family and choices they have made."

She convicted Elena Bobolas of the one offence and fined her $2000.

The magistrate adjourned her sister's sentencing until Wednesday saying she would proceed in her absence if Liana Bobolas didn't turn up.

Australian Associated Press