Europe's rights court on Tuesday ruled against Russia over its refusal to register three associations, saying it was "unacceptable" to do so simply because they were defending LGBT rights.
But one individual applicant's complaint was rejected because of a campaign of insults and threats against the court in response to a previous ruling.
Three associations, which promote lesbian, gay, bisexual and transgender rights, had taken Russia to the European Court of Human Rights after exhausting their legal options at home.
Between 2006 and 2011, Rainbow House, the Movement for Marriage Equality and Sochi Pride House all tried to register as associations with the Russian authorities.
One application was turned down on the grounds that the group would "destroy the moral values of society", lead to a decrease in the population, and violate the rights of Russians who find any display of same-sex relations offensive.
Another was refused over various technical irregularities before being rejected on grounds of "extremism".
The Movement for Marriage Equality was turned down on the grounds that its aim -- same-sex marriage -- was incompatible with "established morality".
"The decisive ground for refusing to register the applicant organisations had been because they promoted LGBT rights," the ECHR said.
"That ground could not be reasonably or objectively justified and had, moreover, amounted to discrimination on the grounds of sexual orientation."
Under the articles of the European Convention of Human Rights, the court found that the associations' rights were violated on several grounds including the right to freedom of association and freedom from discrimination.
- Online abuse -
The court also found that three of the four individual plaintiffs, who were founders or directors of the associations, had suffered discrimination.
But it rejected one complaint filed by the fourth, Nikolay Alekseyev, noting that he had posted threats and insults online after taking exception to a 2018 ECHR ruling in which he was involved.
The court noted that Alekseyev "published judges’ photographs with the captions 'alcoholic', 'drug addict', 'corrupt' and 'European bastards and degenerates'."
He also posted that "it (was) time to set fire to the European Court of Human Rights", the court said.
"These statements clearly exceeded the limits of normal, civic and legitimate criticism," it added.
Despite a warning letter from the Strasbourg-based court, Alekseyev continued his abuse, calling the court's judges "European corrupt scum" and "homophobic", the ruling said.
"The Court considered that Mr Alekseyev’s conduct amounted to contempt for the very institution to which he had applied for the protection of his rights," it noted, ruling his complaint inadmissible.
The court ordered Russia to pay a total of 36,000 euros ($40,000) in damages to the other three individuals as well as their legal costs and expenses.