The planet Rahu and the lords of the sixth and twelfth houses primarily give criminal tendencies, if containing mooltrikona signs.  Rahu's influence is capable of giving all types of anti-social and immoral temptations, which are executed by a strong Mars, or the influence of Mars on the ascendant, third house or the tenth house.  Identification of criminal tendencies is a very useful technique while considering a match for marital alliance, admitting a partner in a partnership and employing somebody for one's business venture.

The influence of a planet is exercised by a planet through placement, conjunction and aspect. The lord of the twelfth house gives vices and intensifies the need for gratification of sensual pleasures for which a person may like to earn a lot of money through gambling, cheating and/or any other means disapproved by the social norms.  The lord of the second house rules status and reputation.  The lord of the sixth house gives inclination for deceptive dealings or raising disputes for personal gains.

Then the influence has to be seen on the houses and planets and has to be synchronized with the operating planetary periods.  The houses involved are first, second, fourth, tenth, twelfth and the sixth while the planets involved are the Sun, the Moon, Venus and Jupiter.  Strong Jupiter and the Sun may be able to fight temptations.  Transit influence on the weak and/or afflicted planets becoming significators for the criminal activities trigger the event. Some amount of such tendencies may be found in the majority of  human beings, but one is hooked and has to suffer from imprisonment due to the close relationship of the lord of the twelfth house and if such afflictions are occurring in the Scorpio and Pisces signs.  The affliction to the Sun indicates trouble through the state while affliction to the Moon indicates a troubled mind.

Let us see it through some illustrations:
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The lord of the twelfth house, Jupiter, closely influences and afflicts the lords of the fourth and ninth houses.  Rahu closely afflicts the ascendant.  The native was charged for criminal conspiracy for theft and was arrested in the sub-period of Rahu in the main period of Saturn.

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The mid-point of the ascendant and the Sun are closely influenced and afflicted by Rahu.  Ketu closely afflicts Saturn.  The lord of the ascendant is placed in the eighth house and is closely associated with the planet of execution, Mars.

During the sub-period of Rahu in the main period of Mercury, the person murdered his wife for which he was convicted and sentenced to life imprisonment.

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This person murdered three persons in a fit of anger and was arrested. Property disputes triggered this violence.

Rahu closely afflicts the lord of the sixth house.  Rahu-Ketu axis is on the mid-point of the houses and afflicts the houses occupied and aspected besides afflicting the Sun.  The lord of the twelfth house, Saturn, is closely conjunct with Mercury and afflicts the same in the tenth house.  At the time of the murder, transiting Ketu was afflicting the natal ascendant, Sun and Ketu by way of an aspect.

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This chart belongs to an alleged manipulator.  The planets Venus, Jupiter and Mercury are under the close influence of Rahu.  Rahu-Ketu axis is on the mid-point of the houses of their location and afflicts the houses occupied and aspected.  The lord of the eighth house is closely afflicting the planet Moon in this nativity.  The lord of the second house is badly placed in the twelfth house.  The lord of the sixth house is placed in the second house and is closely afflicting the lord of the twelfth house.  His so-called manipulations came to light in the sub-period of the Sun and the Moon in the main period of Ketu.

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The lord of the twelfth house is placed in the ascendant and is closely afflicted by Rahu.  Both Rahu and the lord of the twelfth house are closely afflicting the planet Mercury placed in the ascendant.  The functional malefic, Mars, closely afflicts the mid-point of the second house ruling status.  The lord of the second house has gone to the house of disputes.  During the sub-periods of Rahu and Jupiter, the native was involved in numerous controversies and was defamed.  During the sub-period of Saturn he was criminally charged for cheating and his legal complications seriously continued through the sub-period of Mercury, Ketu and Venus in the main period of Rahu.

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The native was tried for indulging in criminal activities and was in serious trouble in the sub-period of Venus in the dasa of Rahu.  He could get relief only in the sub-period of the Moon in spite of contacts at higher levels.  The functionally malefic Mars closely afflicts the ascendant tenth, fourth and fifth houses.  The lord of the twelfth house is closely conjunct with Mercury in the tenth house.  Rahu-Ketu axis is on the mid-point of the houses and afflicts the houses occupied and aspected besides afflicting the Sun.  The lord of the second house has gone to the twelfth house.  His marital life was disturbed and he was addicted to all types of vices in the dasa of Mars.  During the sub-period of Rahu in its own main period, the native's initiative brought him to the company of people of questionable character and landed him in trouble.  The influence of Venus on the lord of the eleventh house brought him fabulous wealth through a profession ruled by Venus.