A spokesman for the pressure group PRoWL will be cross-examined by advocates representing Jeremy Clarkson and his wife, Frances, as the Langness public inquiry moves into its second day today.
Yesterday, Ian Costain presented evidence compiled by Public Rights of Way Langness which, he said, demonstrated disputed paths on the peninsula had been used long enough to be considered public rights of way.
Mr and Mrs Clarkson argue the paths have never been classed as such, while local residents say they have been using them for decades.
The inquiry was ordered by Tynwald at the end of last year, following a dispute which began when the Clarksons diverted a section of the path around their house, to protect their privacy.
It's being held at the Mount Murray Hotel and is being conducted by Roy Hickey, a rights of way expert from the United Kingdom.