Butters grabbed an 81st-minute equaliser, flicking home Paul Reid's cross to leave them seven points adrift of the play-offs.
Leeds took the lead two minutes before half-time when Gylfi Einarsson flicked on David Healy's corner and Clarke Carlisle scored at the second attempt.
Brighton's Charlie Oatway was sent off after kicking out at Simon Walton.
Brighton boss Mark McGhee:
"To go through the whole of January undefeated - I would have taken that at the start of the month," he said.
"I think we deserved a point. I thought they edged the first half and were the better side, although we were still disappointed to go in a goal behind.
"Once we got going in the second half, and put Adam Virgo up front, we deserved our equaliser."
Leeds: Sullivan, Kelly, Butler, Carlisle, Richardson, Walton (Bakke 88), Gregan, Einarsson, Lennon (Spring 78), Deane, Healy.
Subs Not Used: Harrison, Ricketts, Griffit.
Booked: Deane, Bakke.
Goals: Carlisle 43.
Brighton: Yelldell, Reid, Virgo, Hinshelwood, Butters, Mayo, Carpenter, Oatway, Harding (Jones 63), Knight (Nicolas 89), McCammon (Hart 51).
Subs Not Used: May, El-Abd.
Sent Off: Oatway (88).
Goals: Butters 81.
Att: 27,033.
Ref: M Thorpe (Suffolk).