Article 43(1-2) of the Constitution provides that: 1. “Civil proceedings shall not be instituted or continued against the person holding the office of President or performing the functions of that office in respect of which relief is claimed against him in respect of anything done or omitted to be done in his private capacity.
(2) A person holding the office of President or performing the functions of that office shall not be charged with any criminal offence or be amenable to the criminal jurisdiction of any court in respect of any act done or omitted to be done during his tenure of that office or, as the case may be, during his performance of the functions of that office.”
The immunity the President enjoys is not a bar to him suing but to him being sued. There are two (or more) ways in which a President’s immunity may be waived. These are: 1. By Parliament 2. When he sues someone. *other instances relate to presidential election petitions. (see the Chiluba parentage challenge case) .
When a President initiates legal proceedings against someone, he effectively waives his immunity- though only to the extent of those particular proceedings. As a witness, the President is a competent but not a compellable witness.
“Competent” means that one has the legal capacity to be a witness. Every person of sound mind and sufficient understanding is generally competent as a witness.
“Compellable” means one must give evidence when called upon- failure to which would be contempt of court. In this case, no one subpoenaed (Compelled or called) the President to be a witness.
He chose to do so on his own. He cannot therefore later invoke (plead) immunity when subjected to cross-examination because his immunity to that extent only, has been waived.
Article 18(2)(e) provides the accused with the right to: “be afforded facilities to examine in person or by his legal representative the witnesses called by the prosecution before the court, and to obtain the attendance and carry out the examination of witnesses to testify on his behalf before the court on the same conditions as those applying to witnesses called by the prosecution.”
In short, be ye so high, if thou elect to be a witness, thou shall be stripped of immunity & cross-examination shall follow thee like any other ordinary man of the land.
As far as this case proceeds in this manner, Sata has stripped himself of his immunity and can face any charges such as contempt of court, perjery such as lying on oath and hence be imprisoned.