Who's responsible for the death of protesters by sniper fire in Kiev?

Dr Ivan Katchanovsk's paper is very detailed.  I am still reading through it.

From RussiaInsider
Paper presented at the Chair of Ukrainian Studies Seminar at the University of Ottawa, Ottawa, October 1, 2014

The massacre of several dozen Maidan protesters on February 20, 2014 was a turning point in Ukrainian politics and a tipping point in the escalating conflict between the West and Russia over Ukraine. 

The mass killing of the protesters and the mass shooting of the police that preceded it led to the overthrow of the highly corrupt and pro-Russian, but democratically elected government of Viktor Yanukovych and gave a start to a large-scale violent conflict that continues now in Donbas in Eastern Ukraine.

A conclusion promoted by the post-Yanukovych governments and the media in Ukraine that the massacre was perpetrated by government snipers on a Yanukovych order has been nearly universally accepted by the Western governments and the media, at least publicly, without concluding an investigation and without all evidence considered.For instance, Ukraine’s President Petro Poroshenko in his speech to the US Congress on September 18, 2014 again claimed that the Yanukovych government overthrow resulted from mass peaceful protests against police violence, in particular, killings of more than 100 protesters by snipers on February 20, 2014.

The question is which side organized the snipers massacre. This paper is the first academic study of this crucial case of the mass killing. Analysis of a large amount of evidence in this study suggests that certain elements of the Maidan opposition, including its extremist far right wing, were involved in this massacre in order to seize power and that the government investigation was falsified for this reason.

Evidence
Evidence used in this study includes publicly available but unreported, suppressed, or misrepresented videos and photos of suspected shooters, live statements by the Maidan announcers, radio intercepts of the Maidan snipers, and snipers and commanders from the special Alfa unit of the Security Service of Ukraine (SBU), ballistic trajectories, eyewitness reports by both Maidan protesters and government special unit commanders, public statements by both former and current government officials, bullets and weapons used, types of wounds among both protesters and the police, and the track record of politically motivated misrepresentations by the Maidan politicians of other cases of violence during and after the Euromaidan and historical conflicts..........