I think the argument is, if the left abandons law and order, the right will fill the vacuum with authoritarianism. I believe this.
We are not going to de-fund the police. In Ontario the right wing Ford government has reduced the educational requirements of people entering the police force, this is a blatant attempt to keep the police racist and sexist. The left leaning parties have no interest or plans on how to recruit or train the police. The vacuum, means that right wing parties push to get what they want, an authoritarian police force.