I thought that the only case of drunkenness we see in the Harry Potter series was when Winky the house elf got hammered on butter beer.
But I was reminded in chat that there were other cases.
So my question is, who gets drunk in the Harry Potter series?
This includes all canon sources: the books, the movies, the play, Pottermore, and interviews.
Are the teachers at Hogwarts ever publicly intoxicated?
This asks about Hogwarts' teachers; I'm interested in all possible cases.
Excluding the Hogwarts teachers already covered in the other answer, we do see a few other characters in their cups;
Hagrid & Prof. McGonagall (PS)
Flaming Christmas puddings followed the turkey. Percy nearly broke his teeth on a silver Sickle embedded in his slice. Harry watched Hagrid getting redder and redder in the face as he called for more wine, finally kissing Professor McGonagall on the cheek, who, to Harry’s amazement, giggled and blushed, her top hat lop-sided.
Aunt Marge (and probably Mr and Mrs Dursley) (POA)
At last, at long last, the final evening of Marge’s stay arrived. Aunt Petunia cooked a fancy dinner and Uncle Vernon uncorked several bottles of wine. They got all the way through the soup and the salmon without a single mention of Harry’s faults; during the lemon meringue pie, Uncle Vernon bored them all with a long talk about Grunnings, his drill-making company; then Aunt Petunia made coffee and Uncle Vernon brought out a bottle of brandy.
‘Can I tempt you, Marge?’
Aunt Marge had already had rather a lot of wine. Her huge face was very red.
‘Just a small one, then,’ she chuckled. ‘A bit more than that … and a bit more … that’s the boy.’
Sir Cadogan (PoA)
When they reached the portrait hole they found Sir Cadogan enjoying a Christmas party with a couple of monks, several previous Headmasters of Hogwarts and his fat pony. He pushed up his visor and toasted them with a flagon of mead.
‘Merry – hic – Christmas! Password?’
Irish Quidditch fans (GoF)
By the light of the few fires that were still burning, he could see people running away into the woods, fleeing something that was moving across the field towards them, something that was emitting odd flashes of light, and noises like gunfire. Loud jeering, roars of laughter and drunken yells were drifting towards them; then came a burst of strong green light, which illuminated the scene.
Horses (GoF)
He thought the Beauxbatons caravan was likely to be pretty chilly, too. Hagrid, he noticed, was keeping Madame Maxime’s horses well provided with their preferred drink of single-malt whisky; the fumes wafting from the trough in the corner of their paddock were enough to make the entire Care of Magical Creatures class light headed.
Morfin Gaunt (HBP)
‘YOU!’ he bellowed. ‘YOU!’
And he hurtled drunkenly at Riddle, wand and knife held aloft. ‘Stop.’
Riddle spoke in Parseltongue.
The Fat Lady & Violet & Monks (HBP)
‘I’ve got something for you, Harry,’ said Hermione, neither looking at Ron nor giving any sign that she had heard him. ‘Oh, hang on – password. Abstinence.’ ‘Precisely,’ said the Fat Lady in a feeble voice, and swung forwards to reveal the portrait hole.
‘What’s up with her?’ asked Harry.
‘Overindulged over Christmas, apparently,’ said Hermione, rolling her eyes as she led the way into the packed common room. ‘She and her friend Violet drank their way through all the wine in that picture of drunk monks down by the Charms corridor. Anyway …’
A drunken Weasley uncle (DH)
Wandering through the crowd so as to escape a drunken uncle of Ron’s who seemed unsure whether or not Harry was his son, Harry spotted an old wizard sitting alone at a table.
The Oldest Brother (DH)
‘“That very night, another wizard crept upon the oldest brother as he lay, wine-sodden, upon his bed. The thief took the wand and, for good measure, slit the oldest brother’s throat.
Bill, Lupin, Fleur and Harry (DH)
Bill had soon filled all of their goblets; they stood and raised them high in a toast.
‘To Teddy Remus Lupin,’ said Lupin, ‘a great wizard in the making!’
‘’Oo does ’e look like?’ Fleur enquired.
‘I think he looks like Dora, but she thinks he is like me. Not much hair. It looked black when he was born, but I swear it’s turned ginger in the hour since. Probably be blond by the time I get back. Andromeda says Tonks’s hair started changing colour the day that she was born.’ He drained his goblet. ‘Oh, go on then, just one more,’ he added, beaming, as Bill made to fill it again. The wind buffeted the little cottage and the fire leapt and crackled, and Bill was soon opening another bottle of wine.
Harry (again) and Ron Weasley (DH)
‘Oh,’ said Ron. ‘Yeah … well, I’m hungry!’ he added defensively, as his stomach gave an enormous rumble.
‘I got food,’ said Aberforth, and he sloped out of the room, reappearing moments later with a large loaf of bread, some cheese and a pewter jug of mead, which he set upon a small table in front of the fire. Ravenous, they ate and drank, and for a while there was silence but for the crackle of the fire, the clink of goblets and the sound of chewing.
‘Right then,’ said Aberforth, when they had eaten their fill, and Harry and Ron sat slumped dozily in their chairs.
Various hooting Muggle idiots (DH)
‘Where else is there?’ asked Hermione, cringing as the men on the other side of the road started wolf-whistling at her. ‘We can hardly book rooms at the Leaky Cauldron, can we? And Grimmauld Place is out if Snape can get in there … I suppose we could try my parents’ house, though I think there’s a chance they might check there … oh, I wish they’d shut up!’ ‘All right, darling?’ the drunkest of the men on the other pavement was yelling. ‘Fancy a drink? Ditch ginger and come and have a pint!’
Goodwin Kneede (QTtA)
Radulf got a Blooder in the head because old Ugga wasn’t quick enough with his club. The new scoring barrels worked well. Three at each end on stilts, Oona from the inn gave us them. She let us have free mead all night because we won as well. Gunhilda was a bit angry I got back so late. I had to duck a couple of nasty jinxes but I’ve got my fingers back now.
Ron Weasley (CC)
RON: Well, we were only young when we did it the first time and I got very drunk and — well, to be honest, I can’t remember much of it and . . . The truth is — I love you, Hermione Granger, and whatever time says — I’d like the opportunity to say so in front of lots of other people. Again. Sober.
Ron and Neville (CC)
RON: I was having a couple of firewhiskies with Neville in Hogsmeade — as you do — setting the world to rights — as we do — and we were coming back — quite late, very late, and trying to work out which Floo I could use because when you’ve had a drink sometimes you don’t want to use the tight ones — or the turny ones or —
We see Hagrid get drunk many times. In Harry's first year, a mysterious cloaked stranger keeps buying Hagrid drinks in a pub, and gives him a dragon egg (a forbidden item that Hagrid has really wanted for a while), and then Hagrid accidentally reveals the secret of how to get past the three-headed dog Fluffy. He tells half of the tale in Philosopher's Stone chapter 14.
‘Won it [the dragon egg],’ said Hagrid. ‘Las' night. I was down in the village havin’ a few drinks an' got into a game o' cards with a stranger. […]’
The other half we learn in chapter 16.
‘No, we're in a hurry, Hagrid, I've got to ask you something. You know the night you won Norbert? What did the stranger you were playing cards with look like?’
[…]
‘What did you talk to him about, Hagrid? Did you mention Hogwarts at all?’
‘Mighta come up,’ said Hagrid, frowning as he tried to remember. ‘Yeah … he asked what I did, an' I told him I was gamekeeper here … He asked a bit about the sorta creatures I look after … so I told him … an' I said what I'd always really wanted was a dragon … an' then … I can' remember too well, 'cause he kept buyin' me drinks … Let's see … yeah, then he said he had the dragon egg an' we could play cards fer it if I wanted … but he had ter be sure I could handle it, he didn' want it ter go ter any old home … So I told him, after Fluffy, a dragon would be easy …’
‘And did he – did he seem interested in Fluffy?’ Harry asked, trying to keep his voice calm.
Well – yeah – how many three-headed dogs d'yeh meet, even around Hogwarts? So I told him, Fluffy's a piece o' cake if yeh know how to calm him down, jus' play him a bit o' music an' he'll go straight off ter sleep –’
Hagrid then gets drunk in Harry's third year too, when he's afraid he's going to be fired from his teaching job. In Prisoner of Azkaban chapter 6:
Hagrid was sitting in his shirt-sleeves at his scrubbed wooden table; his boarhound, Fang, had his head in Hagrid's lap. One look told them that Hagrid has been drinking a lot; there was a pewter tankard almost as big as a bucket in front of him, and he seemed to be having difficulty of getting them into focus.
Just then, they heard a burst of song. It was Hagrid, making his way up to the castle, singing at the top of his voice, and weaving slightly as he walked. A large bottle was swinging from his hands.
Hagrid and Slughorn got thoroughly hammered after Hagrid's pet acromantula, Aragog's, burial.
“One for Harry . . .” said Slughorn , dividing a second bottle between two mugs, “. . . and one for me. Well” — he raised his mug high — “to Aragog.”
“Aragog,” said Harry and Hagrid together. Both Slughorn and Hagrid drank
deeply.
...
Harry grinned to himself as, unnoticed by either Hagrid or Slughorn (now swapping tales of the illegal trade in dragon eggs) he pointed his wand under the table at the emptying bottles and they immediately began to refill.
After an hour or so, Hagrid and Slughorn began making extravagant toasts: to Hogwarts, to Dumbledore, to elf-made wine, and to —
“Harry Potter!” bellowed Hagrid, slopping some of his fourteenth bucket of wine down his chin as he drained it.
“Yes, indeed,” cried Slughorn a little thickly, “Parry Otter, the Chosen Boy Who — well — something of that sort,” he mumbled, and drained his mug too.
Not long after this, Hagrid became tearful again and pressed the whole unicorn tail upon Slughorn, who pocketed it with cries of, “To friendship! To generosity! To ten Galleons a hair!”
And for a while after that, Hagrid and Slughorn were sitting side by side, arms around each other, singing a slow sad song about a dying wizard called Odo.
“Aaargh, the good die young,” muttered Hagrid, slumping low onto the table, a little cross-eyed , while Slughorn continued to warble the refrain. “Me dad was no age ter go . . . nor were yer mum an’ dad, Harry. . .”Harry Potter and the Half Blood Prince Chapter 22: After The Burial
I think there's quite enough evidence there to show as that Slughorn and Hagrid were well and truly drunk.
If I remember properly, in the fifth book, Harry meets Trelawney drunk because she was fired by Umbridge.
Harry meets Trelawney when she is drunk and goes to hide her sherry bottles in room of requirement, in sixth book not in 5th.
