Under the new legislation organised criminal gangs, particularly those involved in large-scale drug dealing, will not need to be caught for every crime that they commit.
Instead, the government will be able to punish them by seizing their assets without the need for evidence, even if they are acquitted by a court. This attacks the very foundations of our justice system: the presumption of innocence, the bar on double jeopardy, the idea that in order to be punished, you actually have to be proved to have done something specific - and be proved to have done it beyond a reasonable doubt. While irritating to the police and advocates of "law and order", these foundations exist for very good reasons: to protect the innocent and prevent abuses of power. By eroding those standards, it will allow those injustices and abuses to reoccur.
The police and advocates of "law and order" might not care if people are once again banged up for being one of the "usual suspects", and punished on the basis of vague allegations of criminality rather than specific offending - but the rest of us should. Such behaviour is fundamentally unjust, the sort of thing you'd expect in the 70's world of Life on Mars - not in a modern state which supposedly respects human rights.