We conducted this research on behalf of Equalia to evaluate the impact of their campaign to establish CCTV cameras in slaughterhouses. More information about Equalia's campaign is available here on their website.
Due to the desire to reduce animal welfare violations, CCTV cameras have been installed in slaughterhouses in a number of jurisdictions around the world. This has been driven by legal requirements (e.g. England, Israel), agreements between industry and government (e.g. the Netherlands), or retailer requirements (e.g. United States).
There have been no studies testing whether CCTV cameras actually deter violations of animal welfare regulations in slaughterhouses. Until a scientific study calculates the magnitude of the effect of CCTV on compliance with animal welfare regulations, it is difficult to be certain about the exact magnitude of CCTV's impact. However, anecdotal reports from slaughterhouse employees and government officers consistently indicate that CCTV cameras do deter animal welfare violations. This hypothesis is also supported by studies on the effect of CCTV on reducing crime in other contexts. Furthermore, animal welfare violations before and during slaughter risk causing suffering that is extreme.
The slaughterhouse only represents a very small proportion of an animal's life. Even if CCTV cameras do deter animal welfare violations, under certain moral worldviews this may only result in a small welfare improvement when considered across an animal's entire lifespan. Additionally, CCTV can only reduce existing non-compliance which does not affect every animal.
In conclusion, we find that campaigning for CCTV in slaughterhouses is likely to do less good for animals than other campaign options, even if CCTV is likely to reduce non-compliance with animal welfare regulations.
BACKGROUND TO CCTV CAMERAS IN SLAUGHTERHOUSES
In many countries around the world, there are laws that aim to protect the welfare of farmed animals during slaughter. For any welfare regulation to improve the lives of animals in practice, appropriate monitoring and enforcement measures need to be put in place. To monitor the welfare of animals during slaughter, one policy that is often proposed is to install CCTV in slaughterhouses. Under this policy, it is hypothesised that CCTV can deter slaughterhouse owners and employees from violating animal welfare regulations.
There has been no scientific study on whether CCTV in slaughterhouses can deter animal welfare violations in practice. However, there have been many studies on CCTV and reducing crime in other contexts. Research on CCTV and crime in general is grounded in the rational choice perspective (1,2). This is a perspective that emphasises characteristics of the environment, rather than the individual, when an individual is evaluating whether or not to commit a crime. Here, 'rational' does not suggest that people who commit animal welfare violations are perfectly rational. Rather, the term means that potential offenders nevertheless evaluate the potential outcomes of committing a crime, no matter how rapid or bounded that evaluation may be. The rational choice perspective still applies to crimes committed in anger or other intense emotions.
The rational choice perspective describes potential offenders as making a decision based on the effort, risk of detection, potential rewards, provocations, and excuses associated with a crime opportunity (1). CCTV emphasises the ‘risk of detection’, particularly when the CCTV cameras are visible and obvious and/or when crimes are rapidly followed by a response by authorities. The other components in that list may provide insight into preventing animal welfare violations through other means (see final paragraph of report).
CCTV IN SLAUGHTERHOUSES AROUND THE WORLD
Around the world, there are a handful of jurisdictions that have either placed CCTV cameras in slaughterhouses or have considered doing so.
In the United Kingdom (UK), the welfare of farmed animals is under the jurisdiction of the devolved governments (England, Scotland, Wales, and Northern Ireland). Each of these governments has a different policy on CCTV in slaughterhouses.
In England, the use of CCTV in slaughterhouses is mandated by law. This has been the case since 2018, when the Mandatory Use of Closed Circuit Television in Slaughterhouses (England) Regulations 2018 was established. It mandates that footage must be held for 90 days, and inspectors have 'unrestricted access to footage' (3). However, a report written before the regulations were established concluded that the review of footage is likely to be 'intermittent, selective and periodic', which may reduce the value of the footage for deterring animal welfare offences (4). In England, it is accepted that CCTV offers many benefits beyond animal welfare, such as security, training, workplace safety, and auditing and evaluation of facilities (4).
In Scotland, the use of CCTV in slaughterhouses is also mandated by law. This has been the case since 2021, when the Mandatory Use of Closed Circuit Television in Slaughterhouses (Scotland) Regulations 2020 was established. Similarly to the mandate in England, footage must be held for 90 days and can be accessed by inspectors (5).
In Wales, although it is not mandatory to use CCTV cameras in slaughterhouses, many slaughterhouses voluntarily use them. 90% of red meat animals and 97% of poultry animals are killed in slaughterhouses that use CCTV (6). The use of CCTV in slaughterhouses in Wales is required by some certification schemes and is encouraged through government grants (7).
In Northern Ireland, it is also not mandatory to use CCTV cameras in slaughterhouses, but many slaughterhouses voluntarily use them and 99% of slaughtered animals are covered by CCTV (4).
In Israel, the use of CCTV in slaughterhouses is mandated by law. This requirement has been in place since the Ministry of Agriculture ordered, in late 2015, CCTV cameras to be installed in slaughterhouses throughout 2016 (8).
Israel's policy is notable in that camera footage is transmitted live to a central control room at the Ministry of Agriculture (8). This might mean that the CCTV cameras act as a stronger deterrent against violations of animal welfare laws. Indeed, in Israel, a primary justification for the Ministry's decision to install CCTV cameras was the purported ability of CCTV to deter violations of animal welfare laws.
In Spain, the use of CCTV in slaughterhouses has recently become mandated by law. There is currently a transition period in place to allow slaughterhouses to adapt to this royal decree, lasting one year for large slaughterhouses and two years for small slaughterhouses (9).
Under the royal decree (10), slaughterhouses must install a CCTV system that covers areas where live animals are kept (with a specific clause stating that blind spots are not permitted). The footage is owned by the slaughterhouse operator and must be kept for one month. The footage is subject to reviews by government inspectors periodically, when non-compliance is detected, or when there is suspicion of non-compliance. The decree has specific clauses to ensure that the CCTV systems are compliant with EU and Spanish laws on workers' privacy.
In the Netherlands, it is not mandatory to use CCTV cameras in slaughterhouses. However, the government and the slaughterhouse industry reached an agreement where all large and medium slaughterhouses installed CCTV cameras voluntarily (11). These negotiations between government and industry began in 2017, and the first warnings and fines based on camera footage were issued in 2020 (12).
In the Netherlands, CCTV is used for camera inspections on a monthly or twice-monthly basis. During a camera inspection, an inspector looks at around two hours of footage from different days and points around the slaughterhouse (12). Since the CCTV cameras are installed voluntarily rather than as a legal requirement, there are a few weaknesses with the systems. For example, inspectors can only access images during physical camera inspections and not remotely; the images remain the property of the slaughterhouses, and the slaughterhouse owners, not government officers, decide where to place the cameras (12).
In the German state of Lower Saxony in June 2020, an agreement was reached between meat and trade associations, the Lower Saxony association of cities and towns, and the Lower Saxony Ministry of Food, Agriculture and Consumer Protection (13,14). This was a voluntary agreement that set out guidelines for the use of CCTV in slaughterhouses, with no legal requirements. Some employees lodged official complaints relating to data protection (13,14), although many slaughterhouses in Lower Saxony continue to use CCTV today (15). As of 2022, stakeholders in Lower Saxony are developing recommendations for best practice methods relating to CCTV in slaughterhouses (15,16).
The coalition agreement of the federal German government, reached in 2021, states that the government aims to create a legal right for the implementation of CCTV in slaughterhouses above a particular size (17). This indicates that CCTV may become a legal requirement in slaughterhouses across Germany in the next few years.
In the United States (US), CCTV is not legally required in slaughterhouses. Nevertheless, most large slaughterhouses have used CCTV systems for over a decade (18). As of 2018, Arrowsight (a company that audits CCTV footage from slaughterhouses) audited 40% of North America's chicken market, 38% of the pig market, 57% of the cow market, and 68% of the turkey market (18). Since there is likely CCTV footage that is not audited or is audited by other companies, the coverage of CCTV in US slaughterhouses may be even greater than those percentages.
In France, a 2018 law provided for a two-year experiment in which slaughterhouses could voluntarily install CCTV. By February 2020, only three slaughterhouses out of the 934 across France had installed CCTV (19). This voluntary experiment did follow the failure of a bill that would have made CCTV legally mandatory in slaughterhouses (20).
EVIDENCE ON CCTV AND CRIME PREVENTION
CCTV and Deterrence of Crime in Slaughterhouses
There have been no high-quality, empirical studies on whether CCTV cameras improve compliance with animal welfare laws in slaughterhouses. An analysis by the UK Government in 2011 using data on compliance rates found that CCTV cameras do not improve compliance (21). However, the specifics of this analysis are not explained in detail, and the analysis appears rudimentary. The governments of the UK and the Netherlands do publish data on slaughterhouse inspection and compliance rates, but this data is not in a format suitable for conducting an analysis on the effects of CCTV. A government representative from the Netherlands told us that a pilot study found that the probability of detection is ~75 times higher in slaughterhouses with CCTV, although there is no data on whether this translates to higher compliance with animal welfare regulations. However, since probability of detection is a significant factor in the rational choice perspective of crime deterrence, using CCTV is likely to translate to higher compliance.
When asked to give anecdotal evidence, slaughterhouse employees and government officials consistently claim that CCTV cameras do seem to improve compliance with animal welfare laws in slaughterhouses. Ten slaughterhouse employees in the US surveyed by Wigham all reported that CCTV improves animal welfare at slaughter, as long as CCTV footage is audited and staff are held accountable for their actions (18). Moreover, those employees reported that 'the number of misconducts had decreased since the start of CCTV auditing', and that when the quality assurance team member (who is responsible for auditing the footage) is away from the slaughterhouse, the number of non-compliances increases (18). Similar anecdotal evidence from the US is reported by Edwards-Callaway (22). We spoke with government officials from countries where CCTV has been mandatory or widespread, and it was consistently reported that CCTV appears to deter animal welfare violations in slaughterhouses.
The UK government is required, as part of the 2018 regulations that established mandatory CCTV in slaughterhouses, to publish a review of the CCTV mandate. This review is required to be published before 4 May 2023. That review must 'assess the extent to which [the] objectives are achieved'. Therefore, there is a good chance that this review will involve analysing data on whether CCTV does deter animal welfare violations in the UK.
In the jurisdictions that have installed CCTV, officials generally state that CCTV can augment existing inspection and compliance regimes but not replace those regimes (4,6,8).
As noted above, CCTV surveillance in slaughterhouses is believed to have the greatest deterrent effect when non-compliances are rapidly detected and addressed. However, constantly monitoring the footage produced by every camera in every slaughterhouse is not feasible, so most of the footage is not viewed. Increasingly, the monitoring of slaughterhouse footage is conducted using artificial intelligence (AI)¹. This was the motivation behind the AI4Animals (Artificial Intelligence for Animals) system, developed jointly for use in the Netherlands by animal welfare organisations, a meat company, and Deloitte. AI4Animals uses an algorithm to detect video segments that are likely to contain animal welfare violations and flags them for review by humans (24).
CCTV may also improve animal welfare in slaughterhouses beyond the deterrence of welfare violations. CCTV can be used for training and improving processes in the slaughterhouse both proactively and after welfare incidents that do occur.
CCTV and Crime in General
When it comes to the effects of CCTV on crime in general, the strongest piece of evidence is the 2019 systematic review and meta-analysis by Piza et al (2). The meta-analysis included 76 studies conducted over 40 years and constitutes an update of previous meta-analyses. This study found that 'CCTV is associated with a significant and modest decrease in crime'. However, the effects of CCTV depended on the setting, the type of monitoring, and the type of crime. The strongest evidence for the effects of CCTV were observed in car parks and residential areas, with weaker evidence found in other settings. The largest effect was observed when CCTV cameras were actively monitored and when there were multiple interventions alongside this. However, though CCTV was associated with reductions for vehicle crime and property crime, there were no significant effects for violent crime. Notably, significant effects for violent crime have been detected in individual studies due to particular details of how CCTV is implemented (e.g. rapid responses to violations, see below).
Another useful piece of evidence is the 2017 narrative review by Alexandrie (25). Alexandrie was concerned by threats to causal validity in the literature on CCTV. As such, their review selectively focused on randomised experiments and natural experiments, and it included seven studies overall. This review also concluded that CCTV reduces crime in some settings but not others. There were reductions in crime on public streets and at urban subway stations, but no evidence of crime reductions in consumer parking facilities or suburban subway stations.
One expert we spoke to pointed out that most studies on CCTV (including the meta-analysis) focus on public settings. CCTV in private settings, such as retail stores, might be more relevant to CCTV in slaughterhouses. The strongest piece of evidence relating to CCTV in private settings is a 2011 randomised control trial by Hayes and Downs (1). This study tested the effect of two types of CCTV cameras (in-aisle CCTV public view monitors and in-aisle CCTV domes) on the rate of shoplifting of razor blades, a valuable, frequently shoplifted item. The results showed that both types of CCTV cameras caused a notable and statistically significant decrease in the rate of shoplifting. The authors suggest that this decrease occurred because the CCTV cameras increased the perceived risk of detection.
Another expert provided evidence that CCTV cameras would only serve as a deterrent if they are backed up by rapid responses to violations. The efficacy of any deterrent hinges on the certainty of punishment (26,27). (This matches the anecdotal experiences reported by US slaughterhouse employees, above.) In one randomised control trial in New Jersey, scientists tested whether rapid responses to violations observed on CCTV cameras could cause a decrease in the crime rate (27). This study involved CCTV schemes that had been implemented to address violent crime, social disorder, and narcotics activity. The study did find that rapid responses to violations caused the crime rate to decrease, although the effects were larger for violent crime and social disorder than for narcotics activity.
Overall, the general crime literature provides both empirical evidence that CCTV can prevent crime and a theoretical explanation for why it does. There is, notably, variation across studies; the strongest effects seem to be observed in CCTV interventions that are well-implemented, such as those that are accompanied by a rapid response. The theoretical explanation offered for CCTV's preventative effect (increasing the rate of perceived detection) is general, so we expect that this mechanism would also apply to the context of slaughterhouses. The crime experts we spoke to agree with this claim. As such, this body of literature offers evidence that well-designed CCTV interventions would indeed prevent animal welfare violations in slaughterhouses.
SLAUGHTERHOUSES ONLY COVER A SHORT PART OF ANIMALS' LIVES
The slaughterhouse only represents a very small proportion of an animal's life. The evidence outlined in this report does indicate that CCTV could improve animal welfare in the slaughterhouse, but even a moderate improvement in animal welfare - such as the improvement that would arise if CCTV deters animal welfare violations in the slaughterhouse - would represent only a small improvement in the welfare of an animal across their lifespan. Animal welfare improvements that instead apply for a longer period of an animal's lifespan, such as welfare reforms on the farm, may be more impactful than CCTV in slaughterhouses.
Admittedly, animal welfare violations before and during slaughter risk causing suffering that is extreme. Philosophical worldviews that focus heavily on preventing extreme suffering may therefore place a greater importance on deterring animal welfare violations using CCTV in slaughterhouses opposed to welfare reforms on the farm. However, when we are faced with decisions that pull us between different worldviews, an effective choice is one that looks robustly impactful under many philosophical worldviews. CCTV in slaughterhouses may look effective from the perspective of extreme suffering-focused worldviews, but not other worldviews. As such, campaigning for CCTV in slaughterhouses is less effective than other campaign options, including campaigns that improve welfare across animals' lifespans.
This raises the question of whether CCTV could be installed not just in slaughterhouses, but also on farms. However, we spoke to one expert who pointed out that advocating for CCTV cameras on farms may be more difficult. Farmers often live on, or have closer personal relationships with, their farms, so the proposal to install CCTV on farms may trigger more sensitive emotions within the farming industry. CCTV on farms would also result in a very high volume of data that may require either large teams or artificial intelligence to audit appropriately.
CAMPAIGNING FOR CCTV IN SLAUGHTERHOUSES
If an organisation does choose to campaign for the installation of CCTV in slaughterhouses, there are several lessons that can be drawn from the experiences of other countries.
Publishing images of cruelty from undercover investigations could be an indispensable strategy for building public and political support for CCTV in slaughterhouses. In all cases, proposals for CCTV in slaughterhouses gained political and public traction following the media publication of imagery showing animal cruelty obtained in independent investigations by animal advocacy organisations (11,28–31).
Encouraging some slaughterhouses to install CCTV cameras, perhaps through pressure from certification schemes or retailers, might make it easier to subsequently make CCTV a legal requirement across the industry. In England, CCTV cameras were only required by law after a large proportion of slaughterhouses had already installed them. The use of CCTV in slaughterhouses was required by most major food retailers and by RSPCA's Freedom Food certification scheme, and it was recommended by other certification schemes and associations (4). In 2010, around 7% of slaughterhouses had installed CCTV (4). This number increased gradually until 2016, when around 50% of red meat slaughterhouses and 70% of poultry slaughterhouses had adopted CCTV for animal welfare purposes (29). Requirements by certification schemes and retailers encouraged slaughterhouses, particularly those belonging to larger businesses, to adopt CCTV, which in turn may have reduced opposition to the subsequent legal regulations. In fact, when large producers voluntarily adopt new animal welfare practices, those large producers often lobby the government to make those practices legally binding to avoid other producers having an economic advantage (32).
There are also dangers that installing CCTV in slaughterhouses can rebound. Slaughterhouse owners in the Netherlands have argued that, given that CCTV cameras have been installed, companies that perform well on inspections should have fewer physical inspections (12). In contrast, stakeholders in the UK and the US maintain that CCTV cannot replace physical inspections (18,29). Separately, one expert we interviewed pointed out that slaughterhouse employees may commit deliberate acts of animal cruelty in the cameras' blind spots, and this did indeed occur in the Netherlands (33). This highlights the need to ensure that CCTV interventions are well-designed (discussed in 'CCTV and crime in general', above).
The experts we consulted spoke about the critical importance of open communication between the government and the industry. When implementing CCTV in slaughterhouses, it is essential for the government to communicate early and often with slaughterhouse owners to help address any concerns and overcome any challenges. It may also be beneficial to replicate the small grant scheme established by the government in Wales, which helped address complaints by smaller businesses that the costs of purchasing and maintaining CCTV systems would be prohibitive (6). The impact analysis conducted by the UK government could also help to address such complaints (34).
Lastly, it is important to ensure that CCTV cameras installed in slaughterhouses do not infringe upon the rights of employees in terms of data protection (13,14).
Beyond CCTV, there are other ways that animal welfare violations in slaughterhouses may be reduced. Research has found that cruelty to farm animals can be associated with poor work environments or workers who are abused themselves (35,36). Under the rational choice perspective of crime (see above), increasing surveillance is one of several avenues by which crime may be prevented. Another is reducing provocation, which may involve reducing frustrations and stress, avoiding disputes, reducing emotional arousal, neutralising peer pressure, and/or discouraging imitation (1,37). Given the link between poor work environments and animal welfare violations, improving working conditions and workers' wellbeing may be an additional way to reduce animal welfare violations in slaughterhouses.
When it comes to deterring violations of animal welfare regulations, one policy option is to install CCTV in slaughterhouses. Although there have been no direct academic studies on whether CCTV can deter welfare violations in slaughterhouses, anecdotal evidence and studies on CCTV’s effect on other types of crime do suggest that this policy may be effective in reducing non-compliance. However, the slaughterhouse only accounts for a small proportion of a farmed animal's lifespan. Unless one adopts a philosophical worldview that is focused on extreme suffering, we believe that this policy would be less impactful than welfare reforms that benefit animals throughout their lives.
1. Notably, the application of AI in animal agriculture presents many risks to the lives of animals - we are speculating here, but it may be the case that farmers, companies and/or governments that find value in applying AI to a particular area of farm operations may be more predisposed to applying AI to other areas of farm operations. This might contribute to the risk that AI makes animal agriculture more cost-effective and thus hinders the future success of the animal advocacy movement (23). This risk is worth flagging, but the scenario we outline is merely one possibility.
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