The AC Transit board of directors voted yesterday to screw over both low-income riders and voters by raising fares after they promised they wouldn’t. The basic rider fare will jump 14 percent from $1.75 to $2.00. The fare hike will especially hurt low-income riders who depend on AC Transit to get around. The decision also is a slap in the face to voters who approved a $15 million annual parcel tax last November after the board assured them that the tax would avoid a fare increase. AC Transit justified breaking its promise by blaming the recession and cutbacks in state funding, which have led to a $57 million projected deficit.