section 151 of CPC can be used for re-opening evidence or for recalling witnesses but not routinely invoked for reopening evidence or recalling witnesses....

"We may summarize as follows: 
(a) Section 151 is not a substantive provision which creates or confers any power or jurisdiction on courts. It merely recognizes the discretionary power inherent in every court as a necessary corollary for rendering justice in accordance with law, to do what is `right' and undo what is `wrong', that is, to do all things necessary to secure the ends of justice and prevent abuse of its process. 
(b) As the provisions of the Code are not exhaustive, section 151 recognizes and confirms that if the Code does not expressly or impliedly cover any particular procedural aspect, the inherent power can be used to deal with such situation or aspect, if the ends of justice warrant it. The breadth of such power is co-extensive with the need to exercise such power on the facts and circumstances. 
(c) A Court has no power to do that which is prohibited by law or the Code, by purported exercise of its inherent powers. If the Code contains provisions dealing with a particular topic or aspect, and such provisions either expressly or necessary implication exhaust the scope of the power of the court or the jurisdiction that may exercised in relation to that matter, the inherent power cannot be invoked in order to cut across the powers conferred by the Code or a manner inconsistent with such provisions. In other words the court cannot make use of the special provisions of Section 151 of the Code, where the remedy or procedure is provided in the Code. 
(d) The inherent powers of the court being complementary to the powers specifically conferred, a court is free to exercise them for the purposes mentioned in Section 151 of the Code when the matter is not covered by any specific provision in the Code and the exercise of those powers would not in any way be in conflict with what has been expressly provided in the Code or be against the intention of the Legislature. 
(e) While exercising the inherent power, the court will be doubly cautious, as there is no legislative guidance to deal with the procedural situation and the exercise of power depends upon the discretion and wisdom of the court, and the facts and circumstances of the case. The absence of an express provision in the code and the recognition and saving of the inherent power of a court, should not however be treated as a carte blanche to grant any relief. 
(f) The power under section 151 will have to be used with circumspection and care, only where it is absolutely necessary, when there is no provision in the Code governing the matter, when the bona fides of the applicant cannot be doubted, when such exercise is to meet the ends of justice and to prevent abuse of process of court.
11. The Code earlier had a specific provision in Order 18 Rule 17A for production of evidence not previously known or the evidence which could not be produced despite due diligence. It enabled the court to permit a party to produce any evidence even at a late stage, after the conclusion of his evidence if he satisfied the court that even after the exercise of due diligence, the evidence was not within his knowledge and could not be produced by him when he was leading the evidence. That provision was deleted with effect from 1.7.2002. The deletion of the said provision does not mean that no evidence can be received at all, after a party closes his evidence. It only means that the amended structure of the Code found no need for such a provision, as the amended Code contemplated little or no time gap between completion of evidence and commencement and conclusion of arguments. Another reason for its deletion was the misuse thereof by the parties to prolong the proceedings under the pretext of discovery of new evidence.
12. The amended provisions of the Code contemplate and expect a trial court to hear the arguments immediately after the completion of evidence and then proceed to judgment. Therefore, it was unnecessary to have an express provision for re-opening the evidence to examine a fresh witness or for recalling any witness for further examination. But if there is a time gap between the completion of evidence and hearing of the arguments, for whatsoever reason, and if in that interregnum, a party comes across some evidence which he could not lay his hands earlier, or some evidence in regard to the conduct or action of the other party comes into existence, the court may in exercise of its inherent power under section 151 of the Code, permit the production of such evidence if it is relevant and necessary in the interest of justice, subject to such terms as the court may deem fit to impose.
13. The learned counsel for respondent contended that once arguments are commenced, there could be no re-opening of evidence or recalling of any witness. This contention is raised by extending the convention that once arguments are concluded and the case is reserved for judgment, the court will not entertain any interlocutory application for any kind of relief. The need for the court to act in a manner to achieve the ends of justice (subject to the need to comply with the law) does not end when arguments are heard and judgment is reserved. If there is abuse of the process of the court, or if interests of justice require the court to do something or take note of something, the discretion to do those things does not disappear merely because the arguments are heard, either fully or partly. The convention that no application should be entertained once the trial or hearing is concluded and the case is reserved for judgment is a sound rule, but not a straitjacket formula. There can always be exceptions in exceptional or extra-ordinary circumstances, to meet the ends of justice and to prevent abuse of process of court, subject to the limitation recognized with reference to exercise of power under section 151 of the Code. Be that as it may. In this case, the applications were made before the conclusion of the arguments....
We may add a word of caution. The power under section 151 or Order 18 Rule 17 of the Code is not intended to be used routinely, merely for the asking. If so used, it will defeat the very purpose of various amendments to the Code to expedite trials. But where the application is found to be bonafide and where the additional evidence, oral or documentary, will assist the court to clarify the evidence on the issues and will assist in rendering justice, and the court is satisfied that non-production earlier was for valid and sufficient reasons, the court may exercise its discretion to recall the witnesses or permit the fresh evidence. But if it does so, it should ensure that the process does not become a protracting tactic. The court should firstly award appropriate costs to the other party to compensate for the delay. Secondly the court should take up and complete the case within a fixed time schedule so that the delay is avoided. Thirdly if the application is found to be mischievous, or frivolous, or to cover up negligence or lacunae, it should be rejected with heavy costs. If the application is allowed and the evidence is permitted and ultimately the court finds that evidence was not genuine or relevant and did not warrant the reopening of the case recalling the witnesses, it can be made a ground for awarding exemplary costs apart from ordering prosecution if it involves fabrication of evidence. If the party had an opportunity to produce such evidence earlier but did not do so or if the evidence already led is clear and unambiguous, or if it comes to the conclusion that the object of the application is merely to protract the proceedings, the court should reject the application. If the evidence sought to be produced is an electronic record, the court may also listen to the recording before granting or rejecting the application..."