wilfully

Of free will or choice; willingly; voluntarily; gladly; readily.

By design; with set purpose; intentionally; especially, in a wilful manner; as following one’s own will; selfishly; perversely; obstinately; stubbornly.

In law, wilfully is sometimes interpreted to mean

by an act or an omission done of purpose, with intent to bring about a certain result; or

with implication of evil intent or legal malice, or with absence of reasonable ground for believing the act in question to be lawful.

Willingly, of one’s own free will.

Deliberately, on purpose; maliciously.

in a willful manner