I have no party affiliation because parties inherently inhibit democracy. They are unnecessary, dangerous, and moreover incapable of actually representing someone completely anyway as no two persons are likely to ever agree on everything.
But to continue your game, I will list a number of parties and where they fall short in my mind, including a comment on one theory/aspect of the party which they claim to adhere to, but in practice do not:
Democrats:
Agree - The military should be GREATLY reduced. I'm being gracious on this one, since we haven't seen any active movement on this policy issue in at least 8 years. However, over the course of several decades it's one of the issues that Democrats have generally stayed strong on. Military spending is out of control, and a military focus is largely corrupting/defeating.
Disagree - Gun control is good, right, and effective. In point of fact, it is largely ineffective, an abuse of our rights, and generally a bad thing for all involved. Rational regulation isn't inherently bad, but control/abolishment is.
Lie - They stand against the practices of other political ideologies like those of Republicans. In point of fact they almost consistently vote in FAVOR of Republican policies including the Patriot Act, authorization of broad military powers, expanding executive power, corporate bailouts, etc. At least enough do that there is no meaningful opposition or counter to conservative policies.
Republicans:
Agree - Capital Punishment is necessary, strict punishment for committing crimes. Although it has been shown to not actually reduce the overall amount of crime, it does remove the worst offenders (at least in theory), thus preventing things from getting worse. Unless the government turns it's support to empowering individual citizens to remove dangerous criminals permanently, it has to step up as the agent of action and work to protect its citizens.
Disagree - Opposition of labor unions. While it's true that such organizations often become corrupted, the goal of unions is completely laudable and vitally important. Unless government takes an active role against wealth as power, and against corporate corruption and exploitive business practices someone else has to. The ONLY group which has been a successful counter to business abuses is unions.
Lie - Less government is what they work towards. An absolute core ideology of the party, it has been eroded over the years until the party is now FAR more expansionist than even Democrats. Republicans expand the physical size of government, government spending, and government power.
Libertarian:
Agree - Victimless crimes, or crimes purely of morality/ideology, should not be regulated by the government. While there are health concerns concerning prostitution and drugs, they can be addressed through rational regulation instead of criminalization.
Disagree - Taxation is bad. Taxation is not only good, it's an absolute necessity. The level of taxation is questionable, the manner of taxation is debatable, the best agents of collection and distribution are perhaps unknowable - but some taxation is an absolute requirement for a nation to exist.
Lie - Laissez-faire capitalism taken to the extreme supports individual rights. While it's true that government interference in anything runs in opposition to the less is better philosophy, in business and economic matters it is a necessary evil in order to combat greed and the power of wealth. Because those without wealth are wholly at the mercy of those with wealth, and those with wealth generally act in ways harmful to those without, some more powerful balancing force must stand for the poor unless they are otherwise empowered to do so themselves.
Constitution:
Agree - The United States rights and role ends at our border. Noninterventionism is a far preferable international policy.
Disagree - Opposition of pornography . This stances immediately prove that they do not support our founding ideas and documents. Opposition is an abuse of our rights to free speech, and personal pursuit of happiness.
Lie - They defend the principles of our founding documents and forefathers. In point of fact, the rampant zealotry of the party is in direct opposition to our origins. America was not founded as a Christian nation, and was absolutely established with safeguards to prevent the mixing of religious and political powers.
Green:
Agree - The environment/ecology is of central importance to our existence, and the government MUST step up as the agent of action in it's protection.
Disagree - Non-violence doesn't work, however beautiful of a dream it may be. Violence is sometimes necessary and preparation to do violence is required to make it effective.
Lie - I was in a hurry and didn't come up with a good example for this, i'll get back to it later.