The home side started brightly and Steve Jones had already missed a chance before they took the lead in the seventh minute.
Jones delivered a good cross and Butler, under pressure from the Crewe attack, could only find his own net.
Both sides had chances to add to the scoreline, with David Healy going closest for Leeds.
Leeds boss Kevin Blackwell:
"If players think that we can have 16 or 17 good games and then think they can have a day off then they are wrong.
"We got our noses bloodied and Crewe deserved it.
"I want to let the players know that if I can do something I will do it. That's not good enough for me and it's not good enough for them."
Crewe: Williams, Moss, Foster, Walker, Tonkin, Lunt, Billy Jones, Gary Roberts, Vaughan, Steve Jones (Rodgers 90), Higdon.
Subs Not Used: Tomlinson, Rivers, McCready, Johnson.
Goals: Butler 8 og.
Leeds: Sullivan, Kelly, Butler, Kilgallon, Harding (Pugh 81), Moore (Richardson 72), Douglas, Derry, Lewis, Hulse, Healy (Blake 65).
Subs Not Used: Gregan, Bennett.
Booked: Douglas, Lewis, Healy.
Ref: T Kettle (Berkshire).