The age of a younger person matters substantially as under the Sexual Offences Act 2003 any sexual intercourse or any type of sexual activity with a person under the age of 13 is strictly illegal, with rape, assault by penetration and incitement offences carrying a maximum sentence of life imprisonment, and other non-penetration offences carrying a maximum sentence of 14 years depending on case. Where as if a younger person is aged between 13–15, the act does work more flexibly, as for example it is a reasonable defence by an older person to claim they thought a younger person aged 13–15 was aged 16 or over at the time, or for example that two teenagers over the age of 13 were in a relationship before any sexual intercourse took place. It is rare that prosecution would be brought against persons aged 13 or over engaging in sexual intercourse/activity willingly, as long as all persons involved were of similar age, and it did not involve other matters such as violence, abuse or blackmail.