There is a simple concept in American contract law known as "detrimental reliance" which DACA participants should take comfort in.
Why? Because, this principle is so embedded in American jurisprudence that it is difficult to imagine any court -- conservative or liberal -- allowing for the deportation of any lawful DACA participant.
Sure, there will be technical legal contentions that the police power of government is not subject to this sort of contractual obligation and the Obama era documentation may have even required or implied a waiver of any such claims.
But, the DACA participants voluntarily presented themselves to authorities, entered into a program with a reasonable expectation that this information would not be used against them.
The legal and moral arguments against deportation for this group of people are simply too overwhelming for a court to ignore.
Having said this, it is probably true that DACA by way of executive Order was illegal. President Obama may very well have believed it to be so when he signed the DACA executive order. The failure, then and now, belongs to Congress.
The political support for DACA is overwhelming. If Congress can't pass a statutorily sound DACA with the winds of law, politics, and morality all at their backs, it is hard to imagine Congress being able to do anything. Literally, anything.
Of course, Congress doing nothing is why we are here in the first place.
DACA is easy. Congress should do it in six days, not six months.
Comprehensive immigration reform is more difficult, but imperative. We have lived with the consequences of policy by omission and evasion for decades. The victims are immigrants themselves and an economy distorted by dependency on illegal acts and a growing, untaxed, underground economy.
DACA participants will never be deported. The question is whether both Republicans and Democrats will continue to play chicken with their lives and the American economy.