North Carolina is moving forward to legalize hydraulic fracturing — commonly called fracking — after an accidental vote by Democratic state Rep. Becky Carney overrode Democratic Gov. Bev Perdue’s veto on Monday.

Perdue had attempted to veto a Senate bill passed to allow the natural-gas extraction technique in her state, WRAL reported.

The vote was 72-47, with Carney’s accident providing the final vote necessary for the override.

Carney has voted against hydraulic fracturing in the past, and said she spent the day lobbying other Democrats to uphold the veto.

When the vote was taking place, House members had to push either a green button to override the bill or a red button to sustain the veto.