Still used in Canada's Criminal Code at §155 in regards to incest, as in "every one commits incest who, knowing that another person is by blood relationship his or her parent, child, brother, sister, grandparent or grandchild, as the case may be, has sexual intercourse with that person."
In 1956, England published a Sexual Offences Act which stated that:
"Where, on trial of any offence under this Act, it is necessary to prove sexual intercourse ..., it shall not be necessary to prove completion of the intercourse by the emission of seed, but the intercourse shall be deemed complete upon proof of penetration only."
Circa 1957 case, sexual intercourse was defined by the Canadian Code as:
"Sexual intercourse is complete upon penetration to even the slightest degree, notwithstanding that seed is not emitted."
In R v John, the Court held that:
"Sexual intercourse is complete upon penetration of the labia, either majora or labia minora, no matter how little, even though the hymen was never touched nor is there any penetration of the vagina."
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