In federal cases, sentencing begins with "guidelines", but state courts in Texas have no such "guidelines". Sentences vary widely from court to court and from county to county. As far as enhancements are concerned, criminal history can seriously affect the range of punishment, increasing both maximum and minimum sentences. Exactly how the range of punishment is affected depends upon specific factors which are case-specific.
In texas if you have had prior felony convictions at any time and in any State in your adult life the charge can be enhanced for sentencing purposes a third degree becomes a second, and so on. There are minimum and maximum sentence guidelines. That is how he wound up with 20 years
His case could be enhanced with any prior felony whether it's in Texas for another state.
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