Greg Abbott made an unannounced appearance on Facebook live Sunday evening to sign a tough bill banning "sanctuary cities" in the state, thereby avoiding demonstrations opponents planned for later in the week when they thought he was going to put his signature on the legislation.
The American Civil Liberties Union of Texas said the bill - which is called the "show me your papers measure" - "encourages racial profiling by untrained immigration agents" and it "removes democratically elected representatives from office should they fail to comply".
In April, a federal judge blocked the Trump administration from enforcing its threat to take away funds from sanctuary cities.
As Republicans argued that the move was necessary in tackling crime, most police chiefs in Texas opposed it.
Senate Bill 4, also known as the sanctuary cities bill, will ban sanctuary cities in Texas and will require government and law enforcement officials to follow federal immigration laws.
Senate Bill 4 will go into effect on September 1, 2017. Republicans say it is needed to ensure local jails honor requests from federal officials to keep unsafe offenders behind bars.
Protesters rally outside the Texas Department of Insurance building against a ban on so-called sanctuary cities May 1 in in Austin. Saenz said the law will subject people to widespread racial profiling as it is created to alienate "nearly half the state population". Republicans have a strong majority in the Legislature and shoved aside Democratic objections, even as President Donald Trump's efforts to withhold federal funding for sanctuary cities have hit roadblocks in federal courts.
The measure allows police to ask people about their immigration status if they have been lawfully detained.
"Broad rules", such as those in the new law, "will further strain the relationship between local law enforcement and these diverse communities" at a time with "distrust and fear of contacting or assisting the police has already become evident among legal immigrants".
But the Texas and Arizona bills are not identical. The officials can inquire about a person's immigration status during any type of legal detention, including traffic stops. In 2015, Steinle was allegedly killed by undocumented immigrant Juan Francisco Lopez-Sanchez in San Francisco-another sanctuary city.
His Attorney-General, Jeff Sessions, has accused them of allowing illegal immigrants who are violent criminals to go free.
They said immigration was a federal obligation and the law would stretch already meagre resources by turning local police into immigration agents.