Dalai Lama and the Tibet Government in Exile, as well as the western media have never presented any solid evidence or disclosed any reliable source to support their repeated accusation that the Chinese government killed 1.2 million Tibetans between 1949 – 1979. On the contrary, almost all academic scholars and many pro-Tibet advocaters have found that the accusation does not stand on any basis and is even laughable.
One of the main argument of the Exile group to support their genocide allegation is that there were around 6.3 million Tibetans in 1959, and the Tibetan population hardly increased after 30 years. In their 1996 whitepaper “Tibet: Proving Truth from Facts“, the Exile group claimed that based on a 1959 Chinese government newspaper report, there were 6,330,567 Tibetans in China. The number is broken down into 1,273,969, 3,381,064, and 1,675,534 in three different areas (TAR, Kham, Amdo) of the so-called Great Tibet.  However, a scrutiny of the data shows that these three numbers are the exact same numbers published in 1954 by the Chinese government over the above areas. And these numbers referred to the total population of the three areas (including Tibetan, Han, Muslin, etc), but not the Tibetan populations. 
In fact, the total Tibetan population back 1950s was about 2.5 – 2.7 millions according to numerous academic studies, the Chinese national census, and even Tibet government itself. For example, on November 11th, 1950, in an appeal to the United Nations to stop China’s takeover of Tibet, the Tibet government stated “a weak and peace loving people, hardly exceeding 3 million”.  It is impossible that by the end of 1959, the Tibetan population increased to 6.3 million.
A glance at the documents released by the Tibet Government in Exile, one can clearly see a trend that it favors vague data from the newspapers over serious scientific records from academic studies, population census, and historical records.
Therefore, Professor Sautman, a reseacher specialized in studying Tibetan populations, concluded, “What I think these articles show is that there is no evidence of significant population losses over the whole period from the 1950s to the present. There are some losses during the Great Leap Forward but these were less in Tibetan areas than in other parts of China. Where these were serious were in Sichuan and Qinghai, but even there not as serious in the Han areas of China. There are no bases at all for the figures used regularly by the exile groups. They use the figure of 1.2 million Tibetans dying from the 1950s to the 1970s, but no source for this is given. As a lawyer I give no credence to statistics for which there is no data, no visible basis.” 
Professor Goldstein also rejected the allegation: “… the exile leadership … continued to attack Chinese policies and human rights violations in Tibet, often going beyond what the actual situation warranted; for example, with charges of Chinese genocide.” 
Professor Sautman did an extensive and in-depth study on the literature of Tibetan population. In his 2001 paper, he used indisputable data to reject the allegation made by Dalai Lama and the Tibet Government in Exile. For example, “Figures (detailed breakdown of the 1.2 million number) at this level of specificity are meant to impress, but the emigre approach to numbers is quite elastic. In a 1990 book widely circulated by the Tibet Government in Exile, the number of famine victims is given as 343,000, not 413,000. In 1991, the Dalai Lama stated that 200,000 Tibetans had died from starvation, less than half of what had originally been claimed. These discrepancies are not surprising; some of the statistics are based on citation to documents that do not contain the figure at all, or have not been made public by the emigres… Other figures employed in the claim of ‘demographic annihilation’ derive from interviews with Tibetan refugees in India. Such informants are not likely to be reliable. Lois Lang-Sims, a leader of the pro-TGIE Tibet Society of the UK, wrote that statements of refugees examined in the years after the Dalai Lama arrived in India have ‘an extreme and inevitable unreliability‘” 
Professor Sautman’s study is independently confirmed by Professor Goldstein, Co-Director of The Center for Research on Tibet, “One likely factor is that the accounts offered by Tibetan refugees (and apparently also a few individuals in the TAR) are exaggerations or fabrications told to foreigners to garner sympathy and support for the ‘Tibetan cause’… In other words, they were inclined to represent the current situation negatively…. many Lhasa Tibetans harbor deep-seated anger and hostility toward the Chinese, which colors their perception of the current situation and sometimes leads to distortions, exaggerations, and fabrications.“ 
Michael Parenti wrote this in his book “Friendly Feudalism: The Tibet Myth”: “The official 1953 census–six years before the Chinese crackdown– recorded the entire population residing in Tibet at 1,274,000. Other census counts put the population within Tibet at about two million. If the Chinese killed 1.2 million in the early 1960s then almost all of Tibet would have been depopulated, transformed into a killing field dotted with death camps and mass graves–of which we have no evidence. The thinly distributed Chinese force in Tibet could not have rounded up, hunted down, and exterminated that many people even if it had spent all its time doing nothing else.” 
Even Free Tibet Compaign director Patrick French said the allegation has no basis: “the Free Tibet Campaign in London (of which I am a former director) and other groups have long claimed that 1.2 million Tibetans have been killed by the Chinese since they invaded in 1950. However, after scouring the archives in Dharamsala while researching my book on Tibet, I found that there was no evidence to support that figure.” 
 Tibet Government in Exile, Tibet: Proving Truth from Facts, http://www.tibet.com/WhitePaper/index.html, 1996
 First National Census Report, National Bureau of Statistics of China, http://www.stats.gov.cn/tjgb/rkpcgb/qgrkpcgb/t20020404_16767.htm, November 1st, 1954.
 Melvyn C. Goldtein, A History of Modern Tibet, 1913-1951 University of California Press, 1991, pp.746-747
 Barry Sautman, How Repressive Is the Chinese Government in Tibet?, http://www.international.ucla.edu/article.asp?parentid=2732, 2002
 Melvyn C. Goldstein, The Snow Lion and the Dragon: China, Tibet, and the Dalai Lama, University of California Press, 1999
 Barry Sautman, Is Tibet China’s Colony?: The Claim of Demographic Catastrophe, The Journal of Asian Law, Vol 15, No. 1, Fall 2001
 Melvyn C. Goldstein and Cynthia M. Beall, China’s Birth Control Policy in the Tibet Autonomous Region: Myths and Realities, Asian Survey, Vol. 31, No. 3, March, 1991, pp. 285-303
 Michael Parenti, Friendly Fuedalism: The Tibet Myth, http://www.michaelparenti.org/Tibet.html, 2007
 Patrick French, former director of the Free Tibet Campaign in London, New York Times, http://www.nytimes.com/2008/03/22/opinion/22french.html, March 22, 2008