David,
Maybe this question was answered already, and it is purely educational, as I don't condone anyone doing this, but, if someone were to have a DUI expunged, is there still a record of the arrest?
In other words, if someone had a DUI, had it expunged, and then answered falsely that they had never had an alcohol related arrest, would the FAA be able to dig up the paperwork necessary to verify that something did happen?
Just a preliminary, and somewhat obscure, point - as a very general matter, if you've been convicted of something, you can't necessarily get it expunged or sealed. It really depends on the state the conviction is in - some states, for instance, don't allow DUI cases to be expunged or sealed if there's a conviction.
But, assuming that something can be expunged:
I'm honestly not sure of the answer to this question; a lot of it turns on what kind of data mining is done. The bottom line is that once a paper trail exists, you can presume it will always exist in some fashion. Anyway, I'll tell you what I know.
There are several levels of arrest "reporting." First is the local police department - the one that arrests you. Obviously, that PD has a record. The local PD reports to some kind of statewide agency - in Colorado, it's the Colo. Bureau of Investigation (CBI); every state has some version of it. CBI and its counterparts, in turn, report the National Criminal Information Center (NCIC), which is a nationwide criminal database run by the FBI. If its an alcohol conviction, the DMV/MVA probably has a copy, too.
So, there are three levels - local, state, and Federal - of criminal records. Keep in mind that there will also likely be records with the court, the prosecutor's office, maybe even a newspaper office (things like the police beat). A private database also might pick it up.
So, you get your case expunged. As part of that, the Court issues an order
requiring the various state agencies to physically destroy their records (or seal them, in cases of "sealing"). Nothing can be done about something with a private entity, such as a newspaper or private database, because of 1st Amendment and Takings Clause issues.
If the records aren't destroyed, the various custodians are looking at serious sanctions - a lot of places make it a felony to disobey an order of expungment.
So, you can presume that the state agencies - local and state databases, prosecutors, courts, etc. - have complied and the record is gone.
The tricky part is with the NCIC and other Federal databases. State courts don't have the inherent authority to issue Federal officers orders when the officers are acting under Federal authority (and the Feds can't give orders to state officers absent Federal authority to do so, which is actually quite limited).
So, the question that I don't know the answer to is whether Congress has passed a law - or the FBI created a regulation - requiring the NCIC and related databases to abide by state expungment orders. I'd be surprised if that exists.
So, based on my limited knowledge, I would not be comfortable telling someone subject to a mandatory disclosure (FAA, investigation for a security clearance, etc.) that they were safe not disclosing something.
Like I said above, once the paper trail exists, you can never be sure if it's gone. Even if it's supposed to be - the bureaucratic machine is a juggernaut, and once it gets started you have a tough time reigning it in. A flag in one database triggers flags in 15 others, which might trigger another one or two, and so forth.
Here's the bottom line: it's never in your best interests to be dishonest. It will catch up to you. Especially when there are mechanisms in place that are there to catch lies.