Rob Cash stands out among the legions of college students lined up outside the bars on Clinton Street. Dressed in pristine navy blue, with neatly buzzed hair and a clean-shaven face, the 34-year-old nonchalantly bypasses a long line of 20-somethings, nodding his head at the bouncer outside the Summit Bar & Restaurant. For him, there’s no waiting in line at any of the city’s popular clubs.

Inside, Lady Gaga is blaring, the lights are low and colorful, and the place is packed with more than 200 patrons, but one look from Cash is enough to clear a walking path through the dancing mass.

Smiles quickly fade, and heads turn as the husky 5-8 man makes his way to the back of the room. Some even point him out to friends. Cash knows they are staring — and he stares back, straight in the eyes, to see how they will react. After all, it’s his job.

“We watch them drop their drinks,” he says.

Cash is an Iowa City police officer, and at 11:30 p.m. on this particular Saturday, he’s downtown on foot patrol, conducting a bar check, trying to identify and ticket underage partiers.

Those who drop their drinks are, presumably, under 21, and he will ticket them.

Those PAULA fines have become a problem for more than just young adults — this year, the Iowa City City Council has decided to deny liquor-license renewals for bars with PAULA rates greater than one per police visit.

The city councilors have denied those renewals for three bars: Et Cetera, 3rd Base, and the Summit. The owners of the first two have appealed, and they are awaiting a ruling by an administrative law judge. The Summit will also appeal, and the owner has sued the city over the constitutionality of the ordinance.

But the officers assigned to bar checks don’t think much about the possible repercussions that might ensue for establishments. The two to four officers who catch the duty are only responsible for carrying out the law.

Lt. Bill Campbell, the night shift’s watch commander, said the number of officers going bar to bar depends on how many officers are on foot and if there are enough to take care of downtown. From January to September of this year, police visited establishments 1,064 times and issued 580 PAULA tickets during those visits, according to the most recent data available.

It takes a certain type of personality to undertake foot patrol on a busy weekend night, Campbell says. And Cash, a police officer for nine years, is a serious example of those who watch over the deluge.

The Clear Lake, Iowa, native began working the third shift for the Iowa City police after he transferred to from the Muscatine force in 2006. His shift begins at 11 p.m. and ends at 7 a.m., so, obviously, he gets to observe swarms of drunken bar patrons make the downtown scene. Cash prefers the night shift, but not because he takes pleasure in watching those underage drop drinks; it allows him to see his 2- and 4-year-old sons during the day.

“If I worked evenings,” he says, “I’d completely miss them.” He tucks them in before going to work at night and picks them up from daycare the next afternoon.

Cash also appreciates that the night shift sees more action than days — even if much of it is “intoxication and impairment cases” — and less paper gets pushed.

The vernacular is as much a part of the job as spotting drink droppers. Code 4 means the situation is under control, while Code 3 means it needs emergency response. Cash is referred to as No. 29, and his partner on this night is No. 57, Dan Roth.

Then there’s slang that isn’t in the books, but it’s useful on foot patrol. Roth, pointing casually, says “Bogey,” alerting Cash of the pile of orange-ish vomit underfoot.

When Cash is assigned to vehicle patrol, his office is a black Ford Crown Victoria with gadgets and an Internet-accessible computer. On foot patrol, however, his office is migratory: He fills out tickets on garbage can lids and car hoods and keeps everything within reach. In his jacket, for instance, underneath his bulletproof vest, Cash keeps a pad of blank tickets and papers in a Ziplock freezer bag. His vest, the papers, a jacket, and a tool belt make his upper body appear bulky, perhaps intimidating, but it’s good insulation for a chilly night, such as this one, when the temperature hovers around 40 degrees.

Having taken in the first floor of the Summit, Cash walks to the rear and past the restrooms, opens an unmarked door, and ascends a back staircase. The stairs, unlike the rest of the bar, are well-lit, revealing brown-stained walls. Emerging on the upper level, Cash spots his first victim walking to the dance floor: a wide-eyed, scruffy-haired, scrawny guy holding a clear plastic cup of beer. Cash furrows his brow and asks for the man for ID, inspecting it with a flashlight. His instincts were right: the suspect is 19.

“Is there any way you could not give me a ticket?” the man asks, shifting his weight nervously.

Cash unzips his jacket and pulls out his pad. “No. The reason is because you walked up to me holding a beer. You had a purpose in coming here, and you knew what you were doing when you came out tonight.”

The young man scrunches his shoulders.

“I knew when I saw you, you were going to catch me,” he says. “But I appreciate you being nice.”

This is the first of two tickets Cash and Roth dole out at the Summit on this night.

Cash responds with a tone of certainty.

“I can’t say I haven’t been there; I went to college once,” he says. “Let me see you take off your wristbands, and you need to call it a night.”

He did attend to college once on the campus in the town he now patrols. While attending the UI, he also worked as a bouncer and DJ for a now-defunct bar. Cash was a pre-med major but then decided to become a police officer and transferred to the Kirkwood Community College criminal-justice program.

He has no resentment about the drunken bar patrons, but it’s clear that dealing with them all the time gets wearisome. He rolls his eyes as he relates stories of the drunks he’s encountered. One woman thought he was a taxi driver and tried to get into his police car. When she got belligerent and violent, he finally let her in and gave her a ride — to jail.

Another time, on New Year’s Eve, he summoned an ambulance for a woman who wore such a minuscule outfit that she started to get frostbite while waiting in line for a bar.

Once a guy got mad that Cash was giving his girlfriend a ticket and called 911, but Cash phoned dispatch and said not to send anyone. He gave the man a ticket for obstruction of emergency communication. Every weekend, he says, is “sheer repetition.”

Yet, his approach remains cautious. Campbell said the officers’ goal is not to write as many tickets as they can but rather to get control of the drunks before potential violence ensues.

As Cash keeps watch over the Ped Mall, he talks with other officers but doesn’t make eye contact, watching for fights to spark. Every time he or his partner spots a bottle on the ground, they pick it up and throw it away.

“It can become a weapon,” Cash says.

And on this night, he has to stop several men from urinating in public.

The semi-sarcastic man sums up his job description more than once during the course of the night, saying, “I gotta go babysit some more drunk kids.”

The mood can lighten, though, if a drunk is his friend, and Cash encounters one while filling out a ticket on the hood of a police car. It’s a buddy about his age who played with him for the Pearl City Rugby Club Black Bears in Muscatine. The friend puts his arm around Cash and as they joke, a smile glints across the officer’s face. When the friend leaves, Cash says he once arrested the teammate for starting a fight.

“The next day he called me and was like, ‘What happened, what did I do?’ ” Cash remembers.

Cash pauses. “I guess,” he says.

He has to start ticketing and towing cars for a charity race in the morning. It’s not an exciting task, but it’s his job.