To the OP, I looked up this very thing last year. I wanted to know if I could drink my own beer anywhere outside my home, or even bring a few bottles or a keg to a party. In short, the answer is NO!
I gather from the laws that home brew is for consuming in your home, with your family and guests. I believe that goes federally and for Colorado, since homebrew is tax exempt (up to 200 gallons/per 2 person household per year). Basically, if you bring your homebrew outside of your house, you have to be going to a homebrew competition, and the only people that can drink your beer have to be particpants and judges. Oh, and the serving sizes can't exceed six ounces. Obviously, all that is burdensome, and I doubt that many follow the confines of the law. I bring homebrew to parties all the time; and unless the police have probable cause to believe I'm serving untaxed beer at someone's house, and get a warrant, they'll leave it be.
What I would do is leave the keg at home, and fill a growler or bottles with labels on it, so it at least looks like you're drinking/serving taxed beer. I know in Washington Park in Denver the cops don't care if you drink beer openly, out of a keg or cans. Bottles aren't permitted but they're probably only going to bust you if you're falling down drunk, or the cop is being a ******.
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Applicable Statutory Material:
Colorado Revised Statues § 12-47-103. Definitions
As used in this article, unless the context otherwise requires:
(1.5) "Alcoholic beverages" or "alcoholic liquors" means malt, vinous, or spirituous liquors; except that "alcoholic beverages" and "alcoholic liquors" shall not include confectionery containing alcohol within the limits prescribed by section 25-5-410(1)(i)(II), C.R.S.
(11) "Malt liquors" includes beer and shall be construed to mean any beverage obtained by the alcoholic fermentation of any infusion or decoction of barley, malt, hops, or any other similar product, or any combination thereof, in water containing more than three and two-tenths percent of alcohol by weight.
§ 12-47-142. Exemptions
(1) The provisions of this article shall not apply to the sale or distribution of sacramental wines sold and used for religious purposes.
(2)(a) Any provision of this article to the contrary notwithstanding, when permitted by federal law and rules and regulations promulgated pursuant thereto, a head of a family may produce for family use and not for sale such amount of malt or vinous liquor as is exempt from the federal excise tax on such liquors when produced by a head of a family for family use and not for sale.
(b) The production of malt or vinous liquors under the circumstances set forth in this subsection (2) shall be in strict conformity with federal law and rules and regulations issued pursuant thereto.
(c) Malt or vinous liquors produced pursuant to the provisions of this subsection (2) shall be exempt from any tax imposed by this article, and the producer shall not be required to obtain any license provided by this article.
(d) Malt liquors produced pursuant to this subsection (2) may be transported and delivered by the producer to any licensed premise where consumption by persons over the age of twenty-one is authorized for use at organized affairs, exhibitions, or competitions, such as home brew contests, tastings, or judgings. Consumption shall be limited solely to the participants in and judges of such events. Malt liquors used for the purposes described in this paragraph (d) shall be served in portions not exceeding six ounces and shall not be sold, offered for sale, or made available for consumption by the general public.
