The brother of a provincial cabinet minister has pleaded guilty to a charge under the Aquaculture Act.

The case against Donat Robichaud became news when his brother, Deputy Premier Paul Robichaud, was accused of interfering in the case.

Donat Robichaud was accused of violating the terms of his aquaculture licence by not staying within the site he was licensed to use.

On Monday, Donat Robichaud entered a guilty plea in provincial court in Caraquet.

Paul Robichaud told reporters two weeks ago that the charges were minor.

"Because he's my brother, he's making the provincial news today," Paul Robichaud said at the time. "In other situations, a similar situation would not have made the news."

It made the news because Paul Robichaud was accused of using his position in the government to try to block the prosecution.

Paul Robichaud denied it and joked that even if he did try, he didn't succeed.

The accusations of political interference were made in an anonymous letter to the Opposition Liberals.

They turned the letter over to the RCMP, who are looking into the allegation.

The Liberals have called for Paul Robichaud to step down until the conclusion of the RCMP investigation.

Donat Robichaud was ordered to pay a $480 fine plus a 20 per cent victim surcharge.