Section 60.40. §s of evidence; proof of previous conviction; when allowed

1.   If in the course of a criminal proceeding, any witness, including
  a defendant, is properly asked whether he was previously convicted of  a
  specified offense and answers in the negative or in an equivocal manner,
  the party adverse to the one who called him may independently prove such
  conviction.    If in response to proper inquiry whether he has ever been
  convicted of any offense the witness answers in the negative  or  in  an
  equivocal manner, the adverse party may independently prove any previous
  conviction of the witness.
    2.   If a defendant in a criminal proceeding, through the testimony of
  a witness called by him, offers evidence  of  his  good  character,  the
  people  may independently prove any previous conviction of the defendant
  for an offense  the  commission  of  which  would  tend  to  negate  any
  character  trait or quality attributed to the defendant in such witness'
  testimony.
    3.   Subject to the limitations  prescribed  in  section  200.60,  the
  people  may  prove  that a defendant has been previously convicted of an
  offense when the fact of such previous conviction constitutes an element
  of the offense charged, or proof thereof is otherwise essential  to  the
  establishment of a legally sufficient case.