If an officer arrests a person for an offense under Chapter 49 of the Texas Penal Code involving the operation of a motor vehicle or water craft for suspicion of operation while intoxication then there may be a blood draw to determine the blood alcohol concentration level
The key is that the officer must have placed the person under arrest prior to requiring a mandatory blood sample, however, failure to tell the suspect explicitly that he is under arrest may not automatically invalidate the blood sample
. In Nottingham v. State
, the Austin court found that reading the DIC-24 warnings constitutes evidence that the arrest element was met because even though the officer testified he did not arrest the suspect, the DIC-24 says in the body of the warning that the suspect is under arrest.