Why the secrecy about DEWs less-lethals use in Greenham Common?

Greenham Common peace protests started in 1981. Attacks with DEWs complaints were in 1984-85.The Police kept firm denial when t hey could say "yes we used DEWs, they are less brutal than tear gas canisters" we just want to incapacitate you for a 1-2 days to be exhausted as we don't want these large demonstrations.
In my estimate the Police allowed the occupation of Greenham Common to go on until 2000, in order to HIDE what can DEWs do. DEWs could force the protesters to abandon the place within a day! They cause excruciating pain and the fear of disability or death is realistic. But the Police opted not to show off what DEWs can do to 30.000 witnesses in one go, so it seems they tolerated the occupation to be able to keep DEWs as a secret range of weapons, this way it is easier to discredit complaints and deny unauthorised use against people in their homes. And a few dozen people attacked are less credible witnesses than a crowd of 30.000 in one go corroborating all the physical and health symptoms.This caused the belief that there is no Proof about DEWs attacks and that is NOT true at all.