An article which Postol and others submitted to Science & Global Security on the Khan Shaykhun chemical attack was criticized by Bellingcat as being error-filled and methodologically flawed.
The editors of the journal responded to the criticism and decided not to publish the article after they "identified a number of issues with the peer-review and revision process", leading to Postol resigning from the editorial board.
A team from the Middlebury Institute of International Studies at Monterrey said his 2017 analysis of North Korean missile tests contained careless errors and significant factual inaccuracies that lead to incorrect conclusions.
[7] After leaving the Pentagon, Postol helped to build a program at Stanford University to train mid-career scientists to study weapons technology in relation to defense and arms control policy.
[7] In 1990, Postol received the Leo Szilard Prize from the American Physical Society for "incisive technical analysis of national security issues that [have] been vital for informing the public policy debate".
[9] In 2001, he received the Norbert Wiener Award from Computer Professionals for Social Responsibility for his "courageous efforts to disclose misinformation and falisfied test results of the proposed National Missile Defense system".
The then-Ballistic Missile Defense Organization launched an investigation in 1998 and asked a Pentagon advisory board called POET (Phase One Engineering Team), which included two staff members from MIT's Lincoln Laboratory, to review performance of TRW software, using data from the 1997 flight test.
[30] In May 2006, an MIT Ad-Hoc Committee on Research Misconduct Allegation concluded delays in the investigation were caused by a number of factors, including: "initial uncertainty about the applicability of MIT's research misconduct policy to a government [non-MIT] report"; government classification of relevant information, possibly in an attempt to make it unavailable to plaintiffs in the TRW whistle-blower trial; and Postol's failure to provide a clearly written summary of his allegations, which changed repeatedly during the investigation.
The committee also found that Postol repeatedly violated MIT confidentiality rules "causing personal distress to the Lincoln Laboratory researchers, their families and colleagues".
[36] MDA Chief Spokesman Richard Lehner accused Postol and Lewis of basing "their assessment on publicly released photos gleaned from a sensor mounted aboard the SM-3 and postulat[ing] what they perceived to be the interceptor’s impact point although they had no access to classified telemetry data showing the complete destruction of the target missiles, or subsequent sensor views of the intercept that were not publicly released so as not to reveal to potential adversaries exactly where the target missile was struck.
[5] In 2013, Postol and Richard Lloyd, an expert in warhead design at the military contractor Tesla Laboratories, wrote about the Ghouta chemical attack that has taken place during the Syrian civil war.
[41][44][45][46][47] In 2017, Postol criticized the unclassified intelligence assessment released by the Trump administration blaming the air forces of Syrian President Bashar al-Assad for the April Khan Shaykhun chemical attack.
[50][51] On 18 April, Postol published his findings that the crater present in the photographs could not have been the source of the necessary sarin smoke plume, as persons were seen in the video material live at the site, without appropriate protection gear.
[60] In 2019, the Princeton based journal Science & Global Security, on whose editorial board Postol sat,[61] intended to publish a report titled "Computational Forensic Analysis for the Chemical Weapons Attack at Khan Sheikhoun on 4 April 2017" about the Khan Shaykhun chemical attack written by Postol, Goong Chen, Cong Gu, Alexey Sergeev, Sanyang Liu, Pengfei Yao and Marlan O. Scully.
[67] Postol's findings[68] regarding the similarities between the North Korean Hwasong-18 and Russian RT-2PM2 Topol-M intercontinental ballistic missiles were roundly criticized in 2023 by a publication entitled Errors in Postol’s Analysis of the Hwasong-18 from a team of arms control analysts and professors from the Middlebury Institute of International Studies at Monterrey, including Daniel Allen, Madeline Berzak, Michael Duitsman, Decker Eveleth, John Ford, Sam Lair, Jeffrey Lewis, and Tricia White.
Many of these inaccuracies would have been caught by an analyst carefully looking at the totality of the evidence, rather than simply assuming the missiles are the same," and claimed that "in general, Postol works backwards to create a model that fits his assumptions.