:: Lam Thanh Lem also does not seem like the most reliable source either. He's a verifiable assertion from Liem: 
 "Vo Nhan Tri, at the request of the Hanoi government, wrote a book, Croissance économique de la Répubique démocratique du Vietnam (Economic Growth in the Democratic Republic of Vietnam). Having been given this task, the author was allowed to access the documents in the Prime Minister’s archives, where he “found and read a top-secret report on the number of communist cadres falsely accused and executed: 15,000.” Ho Chí Minh, in an attempt to hide the truth, reduced this number to 10,000 when he addressed an assembly of Party members, confessing to having killed a number of “innocent victims.” “Of course, this number of so-called ‘innocent victims’ would be much greater,” according to Vo Nhan Trí." 
 Vo Nhan Tri's Vietnam's Econ. Pol. since 1975, discusses this document at some length and clearly states that it refers to the total number of "innocent victims" executed. Never is there even a hint about them being party members. 
 Vo Nhan Tri's Croissance économique de la Répubique démocratique du Vietnam was published by Éditions en langues étrangères:Hanoi in 1967 (the author worked as an economist for and in the DRV during the 1960's). Hanoi would not have subsidized the leaking of damaging classified documents, so this volume cannot possibly contain the above claim. 

 There is a huge difference between 15,000 innocent party members and 15,000 innocent people, but Liem does not seem to care enough to check. The former claim apparently sounded better to Liem (and to his editor, Frech conservative ideologue J F Revel). So that's one verifiable claim from Liem. What of his non-verifiable claims? I think a dubious tag is warranted, and perhaps an eventual replacemnent an analogous claim (example: Arthur Dommen's refrence to 32,000 executions from a "former cadre" (p.340) sourced to "Land Reform, Rectification of Errors and Intellectual Dissent in North Viet nam, 1954–56,” Saigon Embassy to State, Airgram A-268, November 21, 1973, RG 59, NARA."  Of course the source is Saigon and this must be clearly stated (need to be fair: would we trust Hanoi on the topic of human rights violation in the South?), but at least it's not outlandish.