[Tex-Con-Man]

Is this in response to his investigation(may have something good) into Obama’s Birth Certificate

No.

Justice has been investigating Arpaio for years. This administration has had a hard-on for Arpaio since they were elected.

[Seizethecarp]

“While no formal findings of pattern or practice violations have been made, Mr. Perez said the investigation remains ongoing.”

DOJ has been after Obama with this specific ACLU complaint since March 2009. But Perez still has “no formal findings or pattern or practice violations” so Perez and DOJ have nothing they can charge Arpaio with, yet.

So “the investigation remains ongoing”...meaning the timing of this “announcement” of nothing is very suspicious and points towards it being yet another “don't go there” directed at Arpaio’s eligibility posse, IMO.