Khyber has posted that the statute of limitations is not up multiple times, and done so in highly rated comments. While what the judge did was wrong, the statute of limitations does seem to be up under a careful reading of the statutes. Khyber is pointing out the 10 year limitation for injury to a disabled individual, but is ignoring the specific requirements.
From the statute of limitations link Khyber posted, we have a 10 year and a 5 year term for injury to a disabled individual:
Ten Years- theft of any estate by an executor/administrator. Theft by a public servant of government property, Forgery. Injury to a child, elderly individual, or disabled individual punishable as a felony of the first degree under Section 22.04, Penal Code; Sexual assault, unless there is DNA evidence or if the victim is under 18. Arson;
Five Years
Theft, burglary, robbery; kidnapping; injury to a child, elderly individual, or disabled individual that is not punishable as a felony of the first degree under Section 22.04, Penal Code; abandoning or endangering a child; or insurance fraud;
So, it is only 10 years if is a felony of the first degree under 22.04. Any other felony (under 22.04) would have a 5 year statute of limitations. From the part of section of 22.04 that talks about what sort of felony various things are:
(e) An offense under Subsection (a)(1) or (2) or (a-1)(1) or (2) is a felony of the first degree when the conduct is committed intentionally or knowingly. When the conduct is engaged in recklessly, the offense is a felony of the second degree.
(f) An offense under Subsection (a)(3) or (a-1)(3) or (4) is a felony of the third degree when the conduct is committed intentionally or knowingly, except that an offense under Subsection (a)(3) is a felony of the second degree when the conduct is committed intentionally or knowingly and the victim is a disabled individual residing in a center, as defined by Section 555.001, Health and Safety Code, or in a facility licensed under Chapter 252, Health and Safety Code, and the actor is an employee of the center or facility whose employment involved providing direct care for the victim. When the conduct is engaged in recklessly, the offense is a state jail felony.
(g) An offense under Subsection (a) is a state jail felony when the person acts with criminal negligence. An offense under Subsection (a-1) is a state jail felony when the person, with criminal negligence and by omission, causes a condition described by Subsection (a-1)(1), (2), (3), or (4).
So it is only a felony of the first degree if it is 22.04(a)(1) or (a)(2) (section (a-1) is about caregivers in institutions, and so doesn't apply). What does 22.04(a) say?
Sec. 22.04. INJURY TO A CHILD, ELDERLY INDIVIDUAL, OR DISABLED INDIVIDUAL. (a) A person commits an offense if he intentionally, knowingly, recklessly, or with criminal negligence, by act or intentionally, knowingly, or recklessly by omission, causes to a child, elderly individual, or disabled individual:
(1) serious bodily injury;
(2) serious mental deficiency, impairment, or injury; or
(3) bodily injury.
The difference between (a)(1), (a)(2), and (a)(3) is "serious". Many jurisdictions would use "grievous", but its the same thing: a pretty nasty injury. What specifically does Texas mean, though? For that, we look to Chapter 1 of the penal code, specifically 1.07, "Definitions":
(46) "Serious bodily injury" means bodily injury that creates a substantial risk of death or that causes death, serious permanent disfigurement, or protracted loss or impairment of the function of any bodily member or organ.
Nobody is alleging that the beating required a trip to the hospital, medical care, permanent disfigurement, or anything else that would indicate it was serious bodily injury, rather than bodily injury. This is, at worst, an offence under 22.04(a)(3). It could also be an offence under 22.01(a)(1) (that is, assault), which is a class A misdemeanor. There are a lot of ways to upgrade your assault listed, but none of them to first degree, and regardless the statute of limitations boost requires that it be specifically for an offence in 22.04. None of the boosts seem to apply, anyway. 22.01(b)(2), dealing with family relationships, has the requirement of a previous conviction under subsection (A), or that there be choking, per subsection (B). 22.01(b-1) could also apply, but it requires all 3 conditions of family, previous conviction, and choking (the legislature having specifically included the and as the last bit of 22.01(b-1)(2)).
And that is probably enough detail for now...
In short, statutes of limitations are typically very short. If someone beat you to within an inch of your life and crippled you forever, unless you were a protected class, the limit is only 3 years in Texas. It is a pity this didn't come out 2 years ago. But since there wasn't serious bodily injury, it looks like only a 3rd degree felony, and the limit is only 5 years.