Police are rapidly expanding the use of automatic licence-plate readers. As is the case in SA, this has sparked debate on whether the technology is a crime-fighting tool or a massive invasion of privacy.WASHINGTON, DC – Police in the USA are expanding the use of automatic licence-plate readers, sparking debate on whether the technology is a valuable crime-fighting tool or an invasion of privacy.The technology is still in its infancy in South Africa – but a big factor in the operation of road-tolling, should such tech ever actually start working here (don’t expect it until after the elections, bad karma for the ANC).SOUTH AFRICAN CONCERNThe key issue in SA, just as it is in the US, is whether the authorities have the right to invade your privacy by tracking who you meet, where you go, where you work/shop/socialise… just in case you commit a crime?A recent report by the American Civil Liberties Union (ACLU) warned that these readers - used in patrol cars or fixed locations on streets and highways - collect data on tens of millions of Americans who have committed no wrongdoing, with a potential for privacy abuses.The devices scan licence plate numbers and match these against databases to help police locate stolen cars, criminals or missing children. Backers say this can free police officers from a monotonous task and help solve crimes.With many Americans uneasy over government surveillance of the Internet, the expansion of this technology has sparked concerns about Big Brother.Allie Bohm of the ACLU said: "In our society, it's a core principle that the government doesn't watch people's innocent activities just in case they may connected with a crime.PRIVACY INVASION"In many cases, police are retaining this data indefinitely with few privacy protections. The tracking of people is an invasion of privacy. It can reveal people's political views, religious activities and a lot of other personal information."The ACLU report, based on a survey of hundreds of US police departments, said almost three quarters of police agencies reported using licence plate readers, and 85% planned to increase their use.Only a tiny fraction of the licence plate scans helped point to crimes or stolen vehicles, according to the ACLU survey.It found that for every million plates read in the eastern state of Maryland, only 47 (0.005%), were potentially associated with a stolen car or a person wanted for a serious crime.There have already been abuses. In one reported case, a mayor asked police to track his challenger to expose a relationship with a mistress. In another, police scanned the plates of people at a political protest and then investigated them.Few oppose using the technology to fight crime, but the ACLU and others say keeping data on millions of people for years, or indefinitely, can be troublesome.The report said private companies may end up holding this data with no oversight or privacy protections, noting that one firm holds over 800 million licence plate location records from 2200 law enforcement agencies, including the US Department of Homeland Security.ACLU staff attorney Catherine Crump said in a statement: "We don't object to the use of these systems to flag cars that are stolen or belong to fugitives, but these documents show a dire need for rules to make sure that this technology isn't used for unbridled government surveillance." VALUABLE INFORMATIONDavid Roberts, who heads the technology center for the International Association of Chiefs of Police, said these devices have become "enormously valuable" in fighting and preventing crime.Roberts told AFP: "It automates what is a time-consuming process which officers do on a manual basis. These can trigger automatic alerts and this can have extraordinary value in locating vehicles wanted for a variety of reasons."He noted that the technology can help in "noncriminal" cases such as locating elderly people who may be suffering from dementia.Roberts said surveys by the association indicate around 75% of police departments are using or plan to use licence plate scanners. He said the technology is widely used in other countries, notably Australia, Britain and Canada.Police departments are aware of privacy concerns, but Roberts said these can be minimised by having guidelines in place on use and access of the data, with "strict audits" to ensure that police don't use the data for "fishing expeditions."The association does not recommend a specific length of time to retain data, but urges police department to have policies that allow access only for official law enforcement purposes.Roberts added: "It's not accurate to say this is a tracking system. What these produce is an image of a licence plate in a public space. You still need to access motor vehicle records to find out who the registered owner is."SOME HOPE...Authorities appear to be listening in some cases.In 2013, Virginia's attorney general ruled that police may only use the technology for "active" criminal investigations. And Rockville, Maryland agreed to a system to share its data with a state agency that deletes the information after one year.Even as the debate rages, it remains unclear how effective the technology has been in reducing or solving crime.A 2010 study led by Cynthia Lum at George Mason University was unable to determine whether licence plate readers helped prevent auto theft or other crimes in related hot spots.Lum, a former police officer, said the study was limited in scope. She is seeking to conduct a comprehensive study on the impact on overall crime from the technology.Lum, who heads the university's Center for Evidence-Based Crime Policy, said the technology is appealing because "it automates a process of investigation that police have been using for many years."She noted that the evidence on the effectiveness of scanners is still underdeveloped and said: "There is a chance you might acquire this technology and it might not give you the value in crime prevention that you anticipate."