Conditions to break a precept In the commentary it's said, in order to lie, all four conditions must be met:


An untrue statement
Intention to deceive
Effort is made
Other deceived by what is said


But according to original Vinaya, AFAIK, whether one is deceived or not is irrelevant. I think that is because the intention to lie arises from the doer not the perceiver. But if last condition is not met i.e. a being is not dead, how can we say someone is killing?
According to this description of the vinaya, on page 74+ the conditions for the offence "intentionally deprive a human being of life" includes the result as a necessary condition:


  This rule against intentionally causing the death of a human being is best
  understood in terms of five factors, all of which must be present for there to be
  the full offense.
  
  
  Object: a human being, which according to the Vibhaºga includes human
  fetuses as well, counting from the time consciousness first arises in the
  womb immediately after conception up to the time of death.
  Intention: knowingly, consciously, deliberately, and purposefully wanting
  to cause that person’s death. “Knowingly” also includes the factor of—
  Perception: perceiving the person as a living being.
  Effort: whatever one does with the purpose of causing that person to die.
  Result: The life-faculty of the person is cut as the result of one’s act.
  




On page 245 the conditions for telling a lie involves only two factors:


  A deliberate lie is a statement or gesture made with the aim of
  misrepresenting the truth to someone else. The K/Commentary, summarizing
  the long “wheels” in the Vibhaºga, states that a violation of this rule requires
  two factors:
  
  
  Intention: the aim to misrepresent the truth; and
  Effort: the effort to make another individual know whatever one wants to
  communicate based on that aim.
  


Page 246 says,


  Result is not a factor under this rule. Thus whether anyone understands the
  lie or is deceived by it is irrelevant to the offense.