Minority Tamil legislator Mano Ganeshan said Colombo was tightly controlling the five-day visit of United Nations High Commissioner for Human Rights, Louise Arbour, who is due here Tuesday.
"They want to give her a guided-tour and meet people who will say the right things," said Ganeshan, adding that authorities were out to "stage-manage" the entire visit.
Ganeshan heads the Colombo-based Civil Monitoring Commission, which investigates extra-judicial killings and disappearances.
He said he had nevertheless been able to arrange for the families of victims to meet with Arbour.
Sri Lankan authorities had last week announced that Arbour would not be allowed to travel to the Tamil Tiger-held north, citing security reasons as well as the fear that the rebels would use a visit for propaganda purposes.
"Visiting foreign dignitaries are free to travel to other parts of the country to get a first-hand idea of what's happening on the ground," Human Rights Minister Mahinda Samarasinghe said.