You are making this whole matter too complicated.
It doesn't matter what the crime is.
If some one is in the US 'illegally' they will be deported ... even if they get picked up for JayWalking.
All the other data you put out will be considered when/if the person tries to come back after having been deported.
Talk to an immigration lawyer, if the person has the potential for coming back after they are deported it will help for the immigration lawyer work with the criminal defense attorney ... which is required by the US Supreme court under the "Padilla" case.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
If they are illegal, they will be deported. It is always best to avoid any kind of felony conviction.
My answers are intended only as general legal advice and are not intended to create an attorney-client relationship. There is no substitute for a full consultation with a local experienced criminal defense attorney. For more answers based on my 19 years of experience visit my website, www.austincriminaldefenseattorney.com
The third felony DWI conviction in Texas may be problematic for future adjustment issues if he's even eligible and/or inadmissibility to adjust status if there is an independent basis for that. Any felony conviction or even Class A misdemeanor should be avoided if at all possible. Need to have a close look at the plea agreement to determine whether Chapa-Garza is applicable or not. Key still remains as the other colleagues pointed out that the key is he's here illegally and that's the main crux to his problem.
If you are here illegally, you are deportable. It does not matter whether you commit a crime or not.
Legal disclaimer: The answer provided is general in nature and because not all facts are known, it should not be construed as legal advice. The answer does not create an attorney/client relationship. You should speak to an attorney for further information.