Section 40.05. Entrapment

In  any  prosecution for an offense, it is an affirmative defense that
  the defendant engaged in the proscribed conduct because he  was  induced
  or  encouraged  to  do  so by a public servant, or by a person acting in
  cooperation with a public servant, seeking to  obtain  evidence  against
  him  for  purpose  of criminal prosecution, and when the methods used to
  obtain such evidence were such as to create a substantial risk that  the
  offense  would be committed by a person not otherwise disposed to commit
  it. Inducement or  encouragement  to  commit  an  offense  means  active
  inducement  or  encouragement.  Conduct  merely  affording  a  person an
  opportunity to commit an offense does not constitute entrapment.