Not propping this guy up but what is Texas law with regards to carring a weapon in your car?
OK here we go -
Texas has no laws regarding the carrying of long guns (rifles or shotguns) in motor vehicles.
Texas does not require a person to have a valid handgun license in order to carry a loaded handgun in a motor vehicle or watercraft if the vehicle is owned by the person or under the person’s control. However, Texas generally prohibits intentionally, knowingly, or recklessly carrying a handgun in plain view in a motor vehicle or watercraft, except by handgun license holders carrying the handgun in a shoulder or belt holster.1
Texas law also prohibits intentionally, knowingly, or recklessly possessing or going with a firearm on a passenger transportation vehicle of a school or educational institution except pursuant to written regulations or written authorization of the institution.2 However, Texas passed a law in 2015, which exempted valid handgun license holders from this restriction, effective August 1, 2016.3 Texas law now generally prohbits K-12 school districts from preventing concealed carry license holders from keeping firearms or ammunition in a locked, privately owned or leased motor vehicle in K-12 school parking areas, provided that the firearm or ammunition is not in plain view.4
In 2011, Texas passed a law prohibiting the Department of Family and Child Services from restricting a foster parent from carrying a handgun in a vehicle while transporting a foster child.
Legal (must be concealed if a handgun) as long as you are not committing another crime other than a minor traffic offense, a prohibited person, etc
By being under the influence he was committing a crime and therefore in violation of the law