Peter Andrews, the executive director of corporate services in the Department of Agriculture, Aquaculture and Fisheries, is alleged to have interfered in an investigation in 2011 involving Paul Robichaud's brother, Donat.
The 57-year-old was not in provincial court today in Fredericton, but his lawyer entered the plea on his behalf.
In February 2012, the Opposition Liberals received an anonymous letter alleging that Paul Robichaud interfered with the departmental investigation involving Donat, an allegation the deputy premier denied.
Donat Robichaud later pleaded guilty to "practising aquaculture other than on a site permitted" under the Aquaculture Act and paid a fine.
Eight days have been set aside for Andrews' trial, starting March 5.