Failure of the prosecution to provide any explanation much less a plausible one shows that the investigating agency had no clue about the perpetrators of the crime at the time when it reached the spot or soon thereafter nor did anyone claim to have seen the assailants, for otherwise there was no reason why they could not be named and an FIR registered immediately. Apex Court in State of H.P. v. Gian Chand, (2001) 6 SCC 71 dealt with the effect of failure of prosecution to satisfactorily explain the delay in the lodging of the FIR and declared that if the delay is not satisfactorily explained the same is fatal to the prosecution. This Court observed:

If the prosecution fails to satisfactorily explain the delay and there is a possibility of embellishment in the prosecution version on account of such delay, the delay would be fatal to the prosecution. However, if the delay is explained to the satisfaction of the court, the delay cannot by itself be a ground for disbelieving and discarding the entire prosecution case.

To the said effect is the decision of Supreme Court in Dilawar Singh v. State of Delhi (2007) 12 SCC 641, where this Court observed:

In criminal trial one of the cardinal principles for the Court is to look for plausible explanation for the delay in lodging the report. Delay sometimes affords opportunity to the complainant to make deliberation upon the complaint and to make embellishment or even make fabrications. Delay defeats the chance of the unsoiled and untarnished version of the case to be presented before the court at the earliest instance. That is why if there is delay in either coming before the police or before the court, the courts always view the allegations with suspicion and look for satisfactory explanation. If no such satisfaction is formed, the delay is treated as fatal to the prosecution case.

Reference may also be made to the decisions of Supreme Court in State of Punjab v. Daljit Singh (2004) 10 SCC 141 and State of Punjab v. Ramdev Singh, (2004) 1 SCC 421 which also reiterated the legal position stated in the earlier mentioned decisions.