FORT WORTH (CBSDFW.COM) – A day after being jailed for a probation violation, Ethan Couch was released from the Tarrant County Jail.

According to the Tarrant County Criminal District Attorney’s Office, the Probation Department determined Couch had a “weak positive” THC result on a drug patch which he wore for monitoring purposes and said they “did not have confidence in the result.”

“Until final testing, we cannot tell if the patch result was actually THC. We cannot tell whether the “weak positive” was caused by legal CBD oil or illegal marijuana. When we have proof, we will file a Motion to Revoke Probation,” The Tarrant County Criminal DA’s Office said in a statement Friday.

Couch returned to jail Thursday and was being held with no bond after his community supervision violation warrant showed tested positive for THC, the main psychoactive compound in marijuana.

Ethan Couch (Tarrant County Jail)

Couch, 22, who killed four people in a drunk driving crash in June 2013 when he was a teenager, was originally sentenced to 10 years probation for intoxication manslaughter.

When he violated his probation, he was forced to serve two years in jail.

He violated his probation in December 2015, when video surfaced appearing to show Ethan Couch at a party where there was alcohol.

Couch went to jail after he and his mother, Tonya Couch, fled to Mexico.

Last March, almost one year after he was released from jail, Couch was no longer required to wear an ankle monitor.

At his trial, a psychologist testified Ethan Couch was a victim of “affluenza,” a product of wealthy, privileged parents who never set limits for him.

Last April, a judge has revoked bond for Tonya Couch, 53, after she failed a urine test required as a condition of her bond but don’t specify the substance the urinalysis revealed.