Hmmm...closest I can find is from Meet John Doe. I don't think it's the one you're looking for though.

Quote
TEMPUS

You see, Randolph? That's something you must learn about superheroes -- no matter which way they turn, they're constantly bumping into their own ethics --


SUPERMAN

I'm going to bring you down, Tempus


TEMPUS

Who's 'Tempus?'


SUPERMAN

You've gone too far this time


TEMPUS

What are you gonna do -- impeach me?


SUPERMAN
I'll do what's necessary.


TEMPUS
And as you've already witnessed so will I. You may want to reconsider cooperating with the new administration, Superman ...


Tempus gets into Superman's face.

TEMPUS (CONT'D)

(softly, intensely)
One never knows when one's wife will drive her car off a cliff, does one?


They hold the look for a beat.


SUPERMAN

This is a warning -- stay away from her.


Superman turns and -- WHOOSH!, he's gone. Randolph steps up beside Tempus.

Battle On,
Deadly Chakram

"Being with you is stronger than me alone." ~ Clark Kent

"One little spark of inspiration is at the heart of all creation." ~ Figment the Dragon