A Sikh couple were told they couldn't adopt from a council agency because of "key assumptions made along racial grounds", a court has heard.
Sandeep and Reena Mander said they were told by Adopt Berkshire "not to bother applying" because of their Indian heritage.
Adopt Berkshire and Windsor and Maidenhead council denied that but said the service was prioritising adopters for older children and sibling groups.
A judgement will be made on 6 December.
Lawyers made closing submissions on the final day of the four-day hearing at Oxford County Court.
Adopt Berkshire, which no longer exists, was an adoption service shared by local authorities in the county, including Windsor and Maidenhead where the couple live.
The Manders said they were happy to adopt children of any race, as well as siblings, when they inquired about adoption in March 2016.
Adopt Berkshire claimed the Manders said they did not want to adopt black children.
James Robottom, representing the couple, said their race had been an "overriding reason" for why they were told they could not adopt in Berkshire and should instead look in India.
"The key thing about this case is that key assumptions were made along racial grounds about the children the Manders could adopt in the view of [Adopt Berkshire's] social workers," he said.
"Because of that the Manders were subject to discrimination on the grounds of their ethnicity directly."
Catherine Foster, for Royal Borough of Windsor and Maidenhead council, told the hearing the adoption service had been "caught out trying to be helpful".
She said it was under no obligation to accept the application and that a visit to the Manders' home by a social worker did not need to be made under law.
Ms Foster said varying accounts of what had happened was a result of the Manders having been "emotional, heated and perhaps desperate" after Adopt Berkshire said their case would not be continued in 2016.
The couple, who are being supported by the Equality and Human Rights Commission, have since adopted a child from the United States.