The Law Society of South Africa (LSSA) says it is deeply concerned about increasing "criminal behaviour" in and around court buildings and against legal practitioners.
Its comments were made in reference to an attack on a female advocate in Johannesburg last week, by people wearing Black First Land First (BLF) T-shirts.
"Although we accept the right of political entities and members of the public to protest, violence and destruction can never be condoned," LSSA co-chairpersons, Mvuzo Notyesi and Ettienne Barnard, said.
The law society said assault was a criminal offence and it urged authorities to investigate the matter urgently and to "bring the perpetrators to book".
"The attack involving the woman advocate is doubly unacceptable, having taken place during the 16 Days of Activism against gender-based violence," they added.
Meanwhile, BLF president Andile Mngxitama is in hot water following comments he allegedly made over the weekend at his party's rally in Potchefstroom in the North West, where he reportedly urged his supporters to kill five white people for every one black person that dies because of taxi violence.
His Twitter account was suspended after he repeated the words online.
The Electoral Commission of South Africa (IEC) indicated in a tweet on Monday, that it "note(s) the serious allegations against the BLF's leader. The commission will offer the party an opportunity to clarify its statements in the light of the values of the Constitution. We will assess the matter for an appropriate course of action after receiving a response".
Trade union Solidarity said on Monday that it would approach the IEC and file a complaint against Mngxitama to stop his party from participating in next year's elections.
Solidarity said in a statement that "Section 16(1)(c) of the Electoral Commission Act makes it clear that the chief electoral officer may not register a party if such party is guilty of the incitement of violence or discrimination in accordance with generally accepted grounds".
The Democratic Alliance (DA) said on Monday that it has reported the matter to the South African Human Rights Commission and the Equality Court.
We have reported #AndileMgxithama to the South African Human Rights Commission and the Equality Court following his vile and distasteful remarks which he incites violence against white South Africans.https://t.co/5POYIcrw5i
— Democratic Alliance (@Our_DA) December 10, 2018