1) Criminally 2) Dishonestly 3) Illegally 4) Illegitimately 5) Illicitly 6) Not conforming to the law 1) Illegally 2) Unjustly 
This word is frequently used in indictments in the description of the offence; it is necessary when the crime did not exist at common law, and when a statute, in describing an offence which it creates, uses the word, but it is unnecessary whenever the crime existed at common law, and is manifestly illegal.
[adv] - not conforming to the law
adverb not conforming to the law; `they were unlawfully married`