Section 80. Whoever commences to commit an offence, but does not carry it through, or carries it through, but does not achieve its end, is said to attempt to commit an offence.
Whoever attempts to commit an offence shall be liable to two-thirds of the punishment as provided by the law for such offence.
Section 81. Whoever commences and commits the offence, but does not commit it through, or commits it through, but does not achieve its a good result, such person in said to attempts and commits an offence.
The offence is attempted to commit by whoever, such person shall be punished two-thirds of punishment as prescribed by the law for such offence.
If the act mentioned in the first paragraph is done on account of blind belief, the Court may not inflict the punishment.
Section 82. Whoever attempts to commit an offence, but, on his own accord, desists from carrying it through, or changes his mind and prevents the act from achieving its end, shall not be punished for such attempt to commit the offence. But, if what he has already done comes under the provisions of law as an offence, he shall be punished for such offence.
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Section 86. Whoever does for any reason whatsoever as assist or facility to any other person committing an offence before or late time of committing the offence, even though such assistance or facility is not known by the offender, such assistant deemed to be supporter in committing such offence shall be punished by two-thirds of the punishment as provided for such offence.
link to the full text of the Criminal Code: Thailand-Criminal Code-1956-eng