On a handful of university campuses around the UK, a new weapon in the battle against cheating is being quietly tested.
Many students know that cutting and pasting content can get them into trouble for plagiarism. Universities are already checking work that looks suspicious, to see if it has been copied from elsewhere on the web. But there is growing concern that buying essays for cash is being normalised on social media platforms.
BBC Trending investigations into the promotion of cheating by YouTube stars have led to thousands of videos being taken down and a tightening of precautions by the video platform.
Now software is being developed using what is called "forensic linguistics". This analyses the composition of a document including vocabulary, punctuation and format. It is a technique that has been used by the Federal Bureau of Investigation (FBI) in the United States to piece together profiles of criminal suspects.
"It's like an arms race," says Dr Irene Glendinning, from Coventry University. "We knew students were plagiarising so we now have sophisticated tools to detect it, so the next thing was ghostwriting and the tools don't detect that." That is because work written from scratch, to order, can't be checked against other published text. Coventry is one of the UK universities informally testing the potential of software using forensic linguistics and machine learning. A sample of a student's work can be compared to anything submitted which rings alarm bells with the tutor. "What it will allow us to do is shortcut the detection process to flag up the type of work that is suspicious, so then an expert academic can look at that work."
It could also help provide some evidence to form the basis of a conversation with a student. Once the system is in full operational use, Dr Glendinning believes it could prove to be a powerful deterrent. At the moment it is not illegal to set up a company writing essays, dissertations or other assignments for students.
The companies simply post a disclaimer on their website telling students their products are intended for reference or a guide. Their aggressive marketing tactics, emailing and messaging students directly, leave little doubt this is a lucrative global business. As well as widespread use of sponsorship of young vloggers and other social influencers, some are also going on to city centre campuses with leaflets that imply they are from student support services. But students may also fear being wrongly accused when they simply might have started working harder.
The new software is being developed by the tech company Turnitin, whose vice-president Bill Loller accepts it can never be a complete substitute for human judgement. He insists the new programme will be able to take account of the progress made by students.