What investigation do you want them to do on the gunshot residue point? Dig up the body, swab the hands, and run their own GSR test?
I get that it's inconvenient for one side in the standoff for gunshot residue to be found on their hands. I don't have any reasonable double that there was.
Asking literally anyone except police is a good start. Police are acting as privileged gatekeepers of information and saying "just trust me bro". I expect HN community members to carry themselves to a higher standard here and really dig in. I'm sorry to say it but I'm really starting to doubt your sincerity.
Plenty of experts on primer residue and other forensics topics out there. "Is it possible that this amount of residue is due to the bullets shot at and into Tortuguita and not due to shots fired from a weapon held by him? Do you find it credible that wounds such as those through the palms of Tortuguita coincide with the narrative that he was wielding a gun at the time of his death?" Easy peasy, and I didn't even go to school for journalism. I'm sure there's other means of finding credible information. They could also quote those other activists who were witness to the death and put those quotes on equal footing with those from the police, but they don't.
> I don't have any reasonable double [sic] that there was.
Assuming you meant "doubt": then you're playing a one-sided game while scolding others for what you perceive is one-sidedness. To me it is hypocritical to do so.
I get that it's inconvenient for one side in the standoff for gunshot residue to be found on their hands. I don't have any reasonable double that there was.