Each department in Texas has its own standards.
Many departments have their own academy, some departments get together and 3 or 4 will have an academy together to keep costs down, and of course you can always go to an academy you pay for in your own and hope you can get a job afterwards.
The Texas Commission on Law Enforcement Officer Standards and Education sets the minimum requirements for LEO's.
You can also find info in the Texas Occupations Code chapter 1701. Just run a google search on Texas Legislature or Texas Occupations Code
As far as what each deprtment wants, call or visit the website.
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