Sir Swears Alot/Sophisticated as Hell: As he himself puts it. "If I don't smoke and swear, I'm fucked." Because he is able to not only hold minor and major conversations well despite his constant use of foul language; he is also able to think on his feet better and get himself and his friends out of jail when he does.
It's Not You, It's My Enemies: In the Christmas Special, this turns out to be the reason why his parents abandoned him. His father pissed off the wrong people with his gambling debts and his parents knew that he would be safer in the park with Julian looking after him than he would be going on the run with them.
Jerk Ass: Even on his good days, Jim Lahey is a vicious, bitter, drunken asshole.
I Am the Liquor: Suffers a brief identity crisis in "Say Goodnight to the Bad Guys" when after several failures he starts thinking that maybe he's not the liquor until Randy reassures him.
Randy: You are the liquor, Mr. Lahey. You've always been the liquor.
I Am What I Am: For much of the show his greatest wish was to be reinstated to the police force, and eventually it does happen. At the end of the season, he resigns willingly, feeling that his true calling is to be a drunk trailer park supervisor. note Yes, he did actually specify "drunk". You would expect anything else after the above trope?
May-December Romance: He's clearly quite a bit older than Randy. (The age difference between the actors playing them is over twenty years, and there's no evidence to suggest that the same isn't true for their characters.)
Took a Level in Kindness: He's quite a bit nicer, more patient, and less vindictive after being reinstated as cop. Bubbles also mentions that he used to be nice before the incident that got him fired from the police force the first time.
Lahey's assistant and lover.
Blood Knight: He may not be the toughest but is he is all to happy to fight anybody to keep the park safe.
I Can Change My Beloved: Randy tries several things to deal with Jim's drinking. When he's on the wagon, he actively encourages his sobriety; when he starts sliding, he warns him where it's going to lead; once when went completely into the liquor, he attempted to drink with him to understand him. It never works, and by the end of Countdown to Liquor Day, he's finally had enough.
Though it should be noted that throughout any attempts to help Jim, he never attempts to tone down his own pot smoking despite Lahey's admonishments, in fact it increases.
Lawful Good: He's not actually a bad guy, and in fact, when he's not trying to stop the boys from doing illegal stuff he gets along pretty decently with them. He mostly ends up in conflict with them simply by way of being on the opposite side of the law.
The Pants Come Off: Randy always goes around without a shirt, but when he really gets mad he'll take off his pants, too. When that happens whoever he's angry at is in for a world of hurt.
The reason he takes his pants off is because they are too tight to fight in. When he rips his pants and gets a new, more comfortable pair, he doesn't take them off anymore. Although in "Say Goodnight to the Bad Guys" and "Countdown to Liquor Day" he is back in his old pants without an explanation.
They Call Me Mister Tibbs / Terms Of Endearment: Always refers to Jim Lahey as "Mr. Lahey," despite having been in an intimate relationship with him for years, to the point that on one occasion when the two are fighting, Randy bitterly calls him "James".
The Christmas Special that takes place before the series has Barb finding Randy prostituting himself in front of a burger joint and taking him home out of pity. When she introduces him to Jim (who she is still married to at the time), Randy recognizes him as "Simon" (obviously a fake name that Jim used to hire Randy). When Barb leaves, Jim tries to keep Randy from exposing his secret by telling him to never call him "Simon" again, only "Mr. Lahey".
Sir Swears-a-Lot: When he's on the dope (which is pretty much constantly in Season 7), he basically starts channelling The Tourettes Guy, swearing often and loudly whenever something bad happens to him.
Does Not Like Guns: See, this is how it goes down. J to the R-O-C and the Rockpile are down with being rap musicians, actin' as fences for stolen shit, makin' amateur pornographic art with some fine ladies and stealin' groceries to resell in the park, but they ain't down with usin' guns, nowahteyemzane?
Pretty Fly for a White Guy: Although the episode "The Microphone Assassin" implies that he may actually be biracial. His mother tells him that she was dating a lot of black guys when she became pregnant with him, although she could have just been saying that to cheer him up.
White Gang Banger: A very softcore example, mostly all in his head. As a further twist, Sara and Lucy explain that he genuinely thinks he's black, and his mother implies that he may actually be biracial.
The Starscream: They both screw over Ricky and the boys at the end of Season 4 and become co-trailer supervisors, or so they think as it turned out Barb was pulling their strings all along to buy back the park. The fact they screwed the boys over however remains a plot point through Season 5.
Lady Macbeth: Even after Jim pulls a semi-Heel-Face Turn in season 7, she's incredibly unpleasant towards him and actually encourages him to fall off the wagon.
Manipulative Bitch: She keeps possession of the park by tricking Cory and Trevor into thinking they were buying the park with the Boys' drug money, when in fact she used the money to pay off Sunnyvale's debts and keep the park for herself.
Evil Counterpart: To Ricky and Julian. Like Ricky, he represents an anachronistic character archetype, likes the same things the boys do, is just as rude or abrasive but with none of the redeeming, likeable qualities. However that being said, most of his vile qualities are a smokescreen as been proved by Julian in the first episode, Cyrus is too afraid to use a gun and take a life which suggests deep down he might have a subconscious sense of morality.
George Jetson Job Security: Ricky keeps getting him fired by robbing or stealing from the places Jacob works at. Ricky also got him and Cyrus kicked out of Grade 10 by exposing their cheating on final exams.