A father and son from Vineyard Haven pleaded guilty in Edgartown district court on charges related to heroin possession and distribution.

Adam Robinson, 35, pleaded guilty on June 30 in Edgartown district court to a charge of possessing to distribute class A drug (heroin) . He was sentenced to two years in a house of correction with 66 days of jail credit. Charges of conspiracy to violate drug law and drug violation near school/park were dismissed upon request of commonwealth, defendant consents.

His father, David Robinson, 59, also pleaded guilty on June 30 to a charge of possessing a class A drug (heroin), reduced from possessing to distribute a class A drug. He was sentenced to one year in a house of correction and also given 66 days of jail credit. Charges of conspiracy to violate drug law and drug violation near school/park were dismissed upon request of commonwealth with defendant’s consent.

Both men were arrested April 26 by members of the Martha’s Vineyard Drug Task Force following an investigation into heroin distribution on the Island, police said. Mr. Robinson was arrested by Boston police in March on charges including trafficking a class A drug (heroin).