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A nightclub setting with arms of different people reaching up. One is holding a drink.
Photo by Aleksandar Pasaric.

In a new report, the University of Birmingham team collaborated with the National Crime Agency to carry out a review of available research to find out how much is known about how common this offence is, and the motivation behind it.

Spiking is defined as the covert administration of substances such as drugs or alcohol to somebody without their knowledge or consent. It is commonly associated with drinks but food can also be spiked. There are also reported instances of needle spiking (i.e., spiking via an injection). Motivations for this crime vary and, although some people report doing this as a prank, it can also be done to make someone more susceptible to follow-up crimes such as sexual assault, or robbery.

The researchers found that information on spiking was limited because most studies only explored it within the context of a secondary crime, such as sexual assault, meaning prevalence of spiking is likely under-estimated. They also noted that identifying cases of spiking can be difficult since, even if toxicology results are available, making a distinction between voluntary and involuntary consumption is not always straightforward. To further complicate things, when no substance is found, this does not always mean spiking has not occurred, especially if there is a delay in testing.

People often worry that they won’t be believed if they report spiking crimes that haven’t led to an assault or a robbery but police need to get to a point where they can take action swiftly. It can be hard to prove that a spiking offence has taken place but reporting is important to help understand where and when incidents are occurring

Dr Amy Burrell, University of Birmingham

Dr Amy Burrell, a co-author on the report, said: “People often worry that they won’t be believed if they report spiking crimes that haven’t led to an assault or a robbery but police need to get to a point where they can take action swiftly. It can be hard to prove that a spiking offence has taken place but reporting is important to help understand where and when incidents are occurring.

“Another challenge is that perpetrators may not realise they are committing a crime: it could be as simple as buying somebody a double measure of spirits when they asked for a single, or it could be adding extra alcohol to a drink at home. But spiking is not funny or appropriate, it is an example of people disregarding the importance of consent. We need also to be informing and educating people about these boundaries.”

In terms of motivation for spiking crimes, the researchers also found a lack of robust evidence on spiking itself, since most research was launched only once a secondary offence had been committed. However, research with perpetrators highlights so-called ‘non-offending’ motivations, frequently identified as pranks, having fun, or ‘getting somebody to relax’, suggesting spiking could be more widespread than we think.

Although drink spiking has been a concern for decades, needle spiking is a more recent phenomena. Media reports said that 1,300 incidents were reported to the UK police between September 2021 and January 2022 and evidence shows that media coverage triggers an uptick in reporting. Despite this, none of the research available focuses specifically on injections, suggesting that more research is needed to explore the prevalence and nature of this offence.

The review also found that the most common spiking substance was overwhelmingly alcohol, with drugs such as GHB, Rohypnol, and Ketamine showing up relatively rarely in studies. This does not mean that we should not be concerned about drug spiking, but more attention needs to be paid to the risks of spiking with alcohol.

“Our findings really highlight the need for additional research into spiking to better understand the scale of the problem and how we can address it,” added Dr Burrell. “Our hope is that this can inform a toolkit for police officers to manage and respond to reports of spiking.”