Given the UKs dependence on US intellectual hegemony it is not surprising that UK law and policing and prosecution methods have been heavily influenced by legislation and methods imported from over the pond despite significant differences in the two systems. (Which it can be said have themselves evolved from strategies and tactics used by various repressive regimes from colonial powers to China today). For example, the Protection from Harassment act 1997 and attempts by multinational corporations to use it to stifle protest was influenced by cases in US civil courts whereby corporations sued activists claiming they had been distressed by the protesting which they defined as harassment.

Police Response

Police gang suppression programs for youth and adults (Klein, 1995a) drew impetus from the apparent growth of youth and adult gang problems in the Southwest in the early 1980’s. Gang units were created in law enforcement departments to carry out gang intelligence, investigation, suppression, and prevention functions (Jackson and McBride, 1985; Klein, 1995a). Suppression tactics employed by the Los Angeles Police Department’s (LAPD’s) Community Resources Against Street Hoodlums (CRASH) operations, begun in the early 1980’s, took the form of gang sweeps, hotspot targeting, and intensified patrols to apply pressure on gangs. The model for NETCU then.

Guilt by association

In his book City of Quartz Mike Davis details the new policies and practices introduced in the late 70s and early 80s by state legislators, prosecutors and police in Los Angeles to curb gang-related crime. Members of gangs (identified by various tattoes or bandannas) or those purported to be gang leaders, were to be taken to court and prosecuted because other gang members had committed heinous crimes. This was achieved by using legislation originally developed to combat organized crime- the federal Racketeer Influenced and Corrupt Organizations (RICO) statute which was enacted in 1970. By enacting this legislation the LA district attorney believed that a)youths would be deterred from affiliating to gangs because of the risk of being prosecuted for crimes committed by others and b) the gang as a whole would moderate its activity due to the risk presented to its members. The overall desired effect was for gangs to dissolve.

Obviously this is remarkably similar to the recent prosecution brought in the SHAC trial. As well as relying on obvious gang signifiers the LAPD and other agencies have instigated agencies along the lines of NETCU to gather information on gang members.

"The street gang unit of the City of Riverside police department compiles three related notebooks on a targeted gang. The first notebook contains copies of all incident, arrest, investigative, supplemental, and field interrogation reports pertaining to the gang.
The second notebook contains the personal records of gang members and affiliates, including pictures, prints, rap sheets, and copies of any reports in which their names appear. The third consists of pictures of gang members, individually and together, showing their colors, tattoos, signs, and other indicia of street gang affiliation. The notebook also includes pictures of gang graffiti, with places and dates carefully recorded"

The Use of Conspiracy, Inchoate Offense,
and Solicitation Provisions

So as to augment the punishments meted out to gang members charges of conspiracy, inchoate offence (one that may lead to another offence, for example uploading info on a website that may cause another to commit a crime) and solicitation are used.
"Those who aid and abet the commission of crimes, even though they do not directly participate in the criminal acts themselves, can also be held criminally responsible. Inchoate crimes such as attempt and conspiracy are punishable even though the crime itself is not completed. Conspiracy law also enables prosecutors to reach criminal conspirators who are not at the scene of the crime itself. All these factors mean that traditional criminal law can reach most gang crime".
 http://faculty.missouristate.edu/M/MichaelCarlie/what_i_learned_about/legislature.htm#Conspiracy

Solicitation occurs when one person asks another person to participate in the commission of a criminal offense. When applied to gang activity it aids in the arrest of gang members who have asked other gang members to join them in criminal activity, to commit a crime in order to be accepted into the gang, to prove their loyalty, or for some other reason.

Enhancedments to existing laws

In tandem with this existing laws have been used to prosecute gang members although the laws themselves and the penalties have been enhanced.
Among the more significant enhancements are:

use of a lower standard of proof to increase sentencing levels. For example, in the case of a specific offence it may not be necessary to prove beyond doubt that the offence was committed by the accused, rather that there is a preponderance of particular evidence suggesting that they did.

increasing the amount of time a convicted person may serve in jail or prison by raising the degree of the crime (i.e., from second degree to first degree or from a misdemeanor to a felony).

Enhanced legislation was developed to deal with gang-related criminality and allows the use of a preponderance of the evidence to show that the criminal act was gang-related. Having shown it was gang-related, the court may then raise the level of punishment from a lower degree to a higher degree. In other words, the use of the lower standard of proof makes it easier to impose the enhanced and greater punishment. That has been a notable development in gang-related legislation.

If someone with more time and better knowledge of the law changes here and NETCU practices looks into this it would probably be worth it in terms of getting well up to speed with what NETCU and their friends in FIT are up to. It is handy to see that they are not that smart or original but must rely on copying techniques from the US

Moreover, these schemes as they have developed in the US have been very intensive in their use of time and money- and i believe there have been very high costs of prosecution in the SHAC trial. The end result of this is that the state can only afford to bring so many prosecutions using these methods