The research says women are more likely to listen to this kind of messaging, but men usually boost their piracy habits by 18 per cent.

The paper looks at how well anti-piracy messages work as a put-off, checking the change in TV and film piracy plans among 962 adults compared with what they did before. The three messages tested in the study were copies of three anti-piracy campaigns. Two campaigns used nasty messages to fight piracy, and the third was more educational.

One of the nasty messages was from crime-busting charity Crimestoppers, which warned about the risk of computer bugs, identity theft, losing money and data, and getting hacked. The other message was from the French government, which used a "three strike" system, where pirates were given two letters before their internet was cut off.

The educational message was from the campaign "Get It Right from a Genuine Site", which talked about the cost to the economy and the creative people and pointed consumers away from piracy sites and towards legal ones like Spotify or Netflix.

The study found that one nasty message made women lower their piracy plans by more than half, but men raised their piracy habits. The educational messages did nothing for either men or women.

University of Portsmouth's Centre for Cybercrime and Economic Crime Kate Whitman said the research shows that anti-piracy messages can accidentally make piracy worse due to psychological reactance.

"From an evolutionary point of view, men have a stronger reaction to their freedom being threatened, and so they do the opposite." Also, the study found that people who liked piracy the most showed the most significant changes in piracy plans -- the nasty messages made their piracy even more.