Sorry, but I think you might want to check your sources on that subject. That 180 day provision is almost certainly not applicable to your situation, and wouldn't have been regardless of the disposition of your case. Texas' expunction statute is at this point quite long and convoluted, and there are a lot of people out there who have misinterpreted its provisions.
The only part of the expunction statute that says anything about 180 days is a relatively new part of it (from 2011 legislation) that tries to improve the situation for people who got arrested or ticketed for something that was so off-base that they never even got a court case filed against them. That does happen sometimes, usually because the prosecutor takes a look at the offense report and realizes it's an invalid case or new facts come to the officer's attention soon after an arrest. There's a graduated schedule on when those "never-filed" cases can be expunged, and for Class C misdemeanors, it's 180 days.
But in real life, that's probably not going to help you. Almost all Class C cases are pretty much automatically filed with the court very soon after the ticket or arrest, and that act of filing takes you out of the 180 day expunction eligibility you're looking for. Once the case has been filed, regardless of what eventually happens with it, you typically end up being stuck with the regular two year statute of limitations. There is no way to get a faster expunction by taking a deferred. Either a deferred resulting in dismissal or a straight dismissal will leave you with an expungeable case, but neither disposition has anything to do with that 180 days, because obviously a case has to have been filed to begin with to be deferred or dismissed.
If you do end up with a straight dismissal on this, there are actually a couple of other possibilities for being able to expunge such a case before those two years are up, but both are dependent upon the specific facts of your case, and you're probably not going to be able to determine by yourself whether either would help you. Try contacting an attorney who regularly deals with expunction cases, and that attorney should be able to figure out whether there's any point in proceeding with filing for expunction prior to th statute of limitations expiring. Good luck.
The 180-day rule applies to cases that were never filed. This does not sound like it applies to you. You will have to wait two years from the date you are discharged from the deferred (assuming you are placed on deferred) to file an expunction. It is never a waste of money to hire an attorney on Class C. Ticket attorneys know many technicals way to get cases dismissed. Where they cannot get them dismissed, they can negotiate for reduced fines and reduced probation periods.
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