During questioning of witnesses lawyers are required to follow certain procedural rules. The rules change depending upon whether or not the witness has been called by the lawyer asking the questions. The lawyer who calls the witness to the witness stand asks questions in “examination in chief.” Except in introductory matters or non-contentious matters the questions are not allowed to be leading, that is, they cannot by their nature suggest the answer to the witness.
Another set of rules applies to lawyers questioning witnesses that have been called by the opposition. These questions are in “cross examination”. Examination-in-chief always comes first; then the opposing lawyer is given an opportunity to cross-examine the same witness. When 2 or more accused persons are tried together, the defence lawyers are given an opportunity to cross-examine the witnesses called by other defence counsel before the prosecutor is provided her opportunity to cross-examine the witness.
After the witness has been cross-examined, the lawyer who called the witness to the stand may, but is not required to, ask additional questions to clarify or explain matters that have come up in cross-examination. This is referred to as re-examination. Re-examination is permitted for completeness and/or clarification of evidence that has been raised or introduced by cross-examination that if left alone would be incomplete, misleading or unclear. When re-examination is ended the evidence of the witness is complete.