Where does the phrase "half in the bag", in reference to inebriation, come from?

I check and checked. The following quote from a website is the closest I can find to anyone evening guessing an etymology. It works for me. (I also included all the synonyms for drunk with reference pages!)

"This a guess. When one buys liquor, the clerk usually puts it one of those little bags. And if a person is wanting to be discrete while taking a drink in public, he leaves the bag on." ~~Posted by ESC on April 30, 2007 at 02:04

http://www.phrases.org.uk/bulletin_board/53/messag...

Other synonyms for drunk...

a public mess, ablaze, about, about right, addled, afflicted, afire, aflame, afloat, alcoholic, alcoholled, alkied-up, all gone, all gowed up, ambushed, animated, annihilated, aped, arseholed, at peace with the floor, awry-eyed, bacchanal, bacchanalian, bacchic, backwards, bagged, banged upon sauce, banjo’d, bashed, bassackwards, bat, beery, behind the cork, belligerent, belted, bemused, bender, bent, besotted, bibacious, bibulous, bladdered, blasted, blathered, blatted, blind, blind drunk, blitzed, blitzkrieged, blobbing, blotto, blowing beer bubbles, blown-away, bludgeoned by life, blue, boiled, boiling over, bolloxed, bombarded, bombed, bongoed, boozed, boozer, boozy, bout, boxed, brandy-faced, breathless, broken, buckled, bulldozed, bullet, bunned, buried, bust, butt wasted, buttered, buzzed, cabbaged, cancelled, canned, capernoited, carousing, chemically enhanced, chemically imbalanced, ******, ********, cognacked, comblasted, comblinded, cordial, corked, cormed, corned, count Drunkula, cracked, cranked, crapulent, crapulous, crashed, crinked, crocked, crunk, crushed, cued up, cut, dead to the world, deleerit, delirious, derailed, disguised, disorderly, dizzy, done, doped, down the creek, drenched, drugged, drunk as a fiddler, drunk as a lord, drunk as a piper, drunk as a skunk, drunk as a wheelbarrow, drunk as an owl, drunk as blazes, drunk as chloe, drunk as david’s sow, drunkard, drunken, ecstatic, edged, elevated, embalmed, enthusiastic, euphoric, excited, faced, faded, far-gone, featured, febrile, fermented, fervent, fervid, fevered, feverish, fiddled, fiery, flaked out, flaming, floating, flush, flushed, flustered, fou, franked, frayed, frazzled, fresh, fried, frozen, ****** up, fuddled, full, full as a tick, fully kroizoned, furschnickered, gagged, gassed, gay, giddy, glazed, glorious, glowing, glued, gone, gone borneo, good to go, gooned, goose, greased, groatable, grogged, groggy, half in the bag, half-******, half-cut, half-gone, half-seas over, hammered, hamstered, happy, heated, het-up, high, hooched-up, hooped, hopped-up, horizontal, horseback, hot, howling, humming, humoured, hurting a turtle, impaired, impassioned, in a ditch, in liquor, in rare form, in the bag, in the gutter, in the ozone, in your cups, inebriate, inebriated, inebrious, inflamed, influenced, inspirited, intense, inter pocula, intoxed, intoxicated, invincible, jagged, jar’d, jazzed, jiggered, jugged, juiced, just south of bejesus, keen, kettled, keyed, klangered, kooked, laid out, langered, lashed, leaked, leaning, leaping, leathered, legless, licked, limp, liquored up, lit, lit up, lively, loaded, locked, logged, looped, loopy, lubed up, lubricated, lumga, lush, lushed, lushy, magoogled, marinated, mashed, massacred, maudlin, mellow, Merle Haggard, merry, messed up, minging, mortal drunk, mortalled, muddled, mullered, muzzy, nappy, narcotised, nimtopsical, not so farfrompuken, nuked, obfuscated, obliterated, off the wagon, off ya face, off ya nut, off your trolley, oiled, on a bender, on a campaign, on fire, one over the eight, orgiastic, ossified, out cold, out of it, out of ya tree, out of your mind, over the bay, over your cups, overcome, overtaken, owled, palatic, paralytic, paralytic, partied-out, passionate, pealaid, pickled, piddled, pie-eyed, piffled, pifflicated, pissed, pissed as a fart, pissed as a newt, pissing, pixilated, plastered, plotzed, plowed, plowed over, poisoned, polluted, possessed, potted, potty, potulent, potvaliant, primed, pull a daniel boone, pull a shot-eye, putrefied, quaffed, raddled, rat-arsed, rat-assed, rat-legged, ratted, red-hot, redirected, reeking, reeling, rigid, ripped, roaring drunk, rocked, rooked, roped, rubbered, rummy, saturated, sauced, schlonkered, schnockered, schtumphy, schwacked, screwed, scuppered, seasoned, seeing triple, sewed up, shellacked, shickered, shikker, ****-faced, ****-housed, shot, silly, sizzled, skunked, slambasted, slammed, slapping happy, slaughtered, slewed, slickered, slobbered, slopped, sloppy, sloshed, slozzled, sluiced, smashed, smoked, smuckered, smurfed up, snockered, snooted, so wet you ripple, souzed, soaked, sodden, sopped, sot, sotally tober, sottish, soused, sozzled, spanked, spiffed, spiflicated, spongy, squashed, squiffed, squiffy, staggering, steaming, steamy, stewed, stiff, stiffed, stinking, stinko, stinky, stocious, stoned, stonkered, stooped, stupid, stupified, sunk, swamped, tanglefooted, tanked, tanked-up, tatered, temulent, temulentive, the worse for liquor, three sheets in the wind, three sheets to the wind, throwed off, tiddly, tied one on, tight, tilted, tipped, tipsey, tipsy, tired and emotional, toasted, toe up, topped off, tore down, tore up, torqued, totalled, toxed, toxic, trashed, trolleyed, trollied, trounced, trousered, tuned up, tuned-out, tweeked, twisted, under the influence, under the table, under the weather, unsober, vulcanized, walloped, wankered, wankered, wasted, wearing a wobbly boot, well-bottled, wellied, well-oiled, whacked, whacked out, whiskeyfied, whiskey-frisky, whittled, wicked retarded, wiggy, wiped-out, wobbly, wombled, woozy, wracked, wrecked, zealous, ziced, zipped, zonked, zoused, zozzled

http://www.joppeluiten.nl/drunk_in_english.htm

here are other lists:

http://freaky_freya.tripod.com/Drunktionary/E-H.ht...

http://dack.com/booze/

Half In The Bag

While I agree with the other answer posted (drunks in public places often drink from paper bags), the police vans that once picked up drunks from the streets were sometimes called "bags." (Comparable to "paddy wagon" without the Irish slur.) "We bagged 7 drunks in one trip through the park. Those two over there are half in the bag. We'll get 'em next trip." I think this is a carryover from terminology used by dog catchers who used a net to "bag" stray dogs.

-mtg

This Boston Globe article suggests it come from the term “bag o’ beer” which meant a quart of cheap porter mixed with ale back in 1909.

From http://www.boston.com/bostonglobe/ideas/articles/2...

"

Farmer and Henley’s 1890 slang dictionary lists “To PUT or GET ONE’S HEAD IN A Bag” as printers’ and sailors’ slang for “drink,” with a quote from an 1887 issue of the Saturday Review: “It is slang, and yet purely trade slang, when one printer says of another that he has GOT HIS HEAD IN THE BAG.”

The “bag” in question may well be the “bag o’ beer” cited in James Redding Ware’s 1909 dictionary of Victorian slang, shorthand for a quart of a blended brew - “half of fourpenny porter and half of fourpenny ale.” By the 1940s, we have “in the bag” (and “half in the bag”), “bagged,” and, yes, “tie a bag on.” The last phrase could have been influenced by similar slang for “eat” - “to put on/tie on the nosebag”

"

Half-in-the-bag....Means...basically HALF DRUNK.