accidental,
inadvertent happening by chance or unexpectedly or unintentionally ; "with an inadvertent gesture she swept the vase off the table"; "accidental poisoning"; "an accidental shooting"
knowingly,
wittingly with full knowledge and deliberation; "he wittingly deleted the references"
unintentional,
unplanned,
unwitting not done with purpose or intent; "an unintended slight"; "an unintentional pun"; "the offense was unintentional"; "an unwitting mistake may be overlooked"
