Mental capacity

In order to possess capacity to consent to sexual relations, a person clearly had to have a basic understanding of the mechanics of the physical act and clearly had to have an understanding that intercourse might lead to pregnancy. Further, capacity required some grasp of issues of sexual health.

However, the knowledge required was fairly rudimentary. It should suffice if a person understood that sexual relations might lead to significant ill-health and that those risks could be reduced by precautions. Although the moral aspect was an important component in sexual relations it could have no specific role in a test of capacity. As to the emotional component, the court could do no more than ask whether the person whose capacity was in question understood that they had a choice and that they could refuse.