A young man who supplied the capsules of MDMA that his girlfriend took before she died has been sentenced to a 12-month good behaviour bond and fined $800.

Jordan Duffy, 20, and Janie Panton Roberts, 21, were at a party at Petersham Inn on June 4 when he supplied her with three MDMA capsules.

The court heard that Duffy bought pills from a work colleague at the club and gave three to Ms Panton Roberts, a former Mackellar Girls School student, and took some himself.

The next morning, the pair were at a house in Marrickville, when she fell ill. She had died by the time paramedics arrived.

Duffy last year pleaded guilty to one count of supplying a prohibited drug.

Ms Panton Roberts' mother, Kerry Roberts, stormed out when the sentence was delivered in the Newtown Local Court on Friday afternoon.

An emotional Ms Roberts had previously told the court that Duffy should not get a "a slap on the wrist" and that she wanted him to receive a jail sentence.

Outside court, Ms Roberts said:  "My baby's dead and he gets [twelve] months good behaviour." View More