The White House refuses to respond to the petition to investigate Chris Dodd, even though it got 25,000+ signatures...

... and they promised to respond, if there were that many signatures. 

To be fair, saying we're not going to respond is a kind of response. In fact, it's an especially meaningful response in the context where one is obligated to respond.

Or perhaps they were never obligated. Look at the text of the refusal to respond:

Why We Can't Comment

Thank you for signing this petition. We appreciate your participation in the We the People platform on Whitehouse.gov. However, consistent with the We the People Terms of Participation and our responses to similar petitions in the past, the White House declines to comment on this petition because it requests a specific law enforcement action.

The link is in the original text. Maybe you're not supposed to click on it. Maybe you're just supposed to assume that it goes to a page of official terms of participation that would show that there was always an exception for petitions that request a specific law enforcement action. But if you click, you'll see it just goes to the currently active petitions, and if you search that page for the word "terms" or "participation," you get nothing.

I spent some time looking for the terms of participation, and I couldn't find any. What is the rule? Was it really a rule? I see a button "Helpful Hints," but the only hint is to check your spelling and grammar because you won't be allowed to edit or delete.

And what were the "similar petitions" that were rejected in the past? I'd like to see how much like those other petitions this one was and also whether all similar petitions were rejected. What if the "similar" ones were the ones that named individuals the administration chooses to protect?