1.  A defendant may not be convicted of any offense upon the testimony of an accomplice unsupported by corroborative  evidence tending  to connect the defendant with the commission of such offense.

  2.   An "accomplice" means a witness in a criminal action who, according to evidence adduced in such action, may reasonably be considered to have participated in:

  (a) The offense charged; or

  (b) An offense based upon the same or some of the same facts or conduct which constitute the offense charged.

  3.  A witness who is an accomplice as defined in subdivision two is no less such because a prosecution or conviction of himself would be barred or precluded by some defense or exemption, such as infancy, immunity or previous prosecution, amounting to a collateral impediment to such a prosecution or conviction, not affecting the conclusion that such
witness engaged in the conduct constituting the offense with the mental state required for the commission thereof.