PETALING JAYA - Sabah's dramatic population spike was among the greatest concerns of witnesses in the inquiry.
The RCI said that in 2007, a memorandum submitted by Parti Bersatu Sabah (PBS) to then Prime Minister Tun Abdullah Ahmad Badawi, had pointed out a huge rise in population from 1970 to 2000.
PBS had alleged that the increase in population in Sabah was 301 per cent compared to 106 per cent in Sarawak.
"It was quite evident that the biggest increase was in 1991, when the statistics (quoted by PBS) registered an increase of 78 per cent," said the RCI in its report.
PBS in its memorandum also cited figures from the Statistics Department showing that the population increase for KadazanDusunMurut (KDM) was 162 per cent, while the spike for Bajau and Iranun was 344 per cent.
The most drastic increase was the 1,552 per cent spike in the number of Malays.
"In the absence of any evidence to the contrary, these figures can be perceived as credible even though no officials from the Statistics Department have been called to verify the accuracy," said the RCI.
A paper presented by the United Pasok Momogun Kadazandusun Murut Organisation (Upko) also touched on the "unnatural" population growth in Sabah over the years.
Based on its statistics, the growth rate of the KDM community recorded 236 per cent between 1960 and 2000 while the growth rate for Muslim bumiputras was 631 per cent during the same period.
Apart from the population spike, the RCI found there was ample evidence that the huge influx of illegal immigrants to Sabah from 1978 was essentially due to economic reasons.
"On the evidence before us, it is reasonable to assume that there was massive unemployment in southern Philippines and Indonesia where they originated.
"In contrast, Sabah was rich in natural resources. There were ample job opportunities in most sectors of its economy," said the RCI.
Another factor identified includes the alleged territorial claim to Sabah by the Philippine government as there is some evidence that many Filipinos still perceive the state to be part and parcel of the Philippines.