Detroit may be booming, but the revival has a downside that's got some people crying foul: $45 parking tickets.

If a new lawsuit is any indication, those pesky fines could prove costly for the city of Detroit, which has been hit with a proposed class action lawsuit over the millions it has made at the meter.

The lawsuit filed in U.S. District Court by a Detroiter and a suburbanite alleges the city is ripping off residents and visitors through excessive parking tickets and late fines that they claim are unconstitutional. They claim the city is taking money from people that it is not entitled to under law.

According to the lawsuit, the city of Detroit has issued about 300,000 parking tickets annually over the last three years, during which the city implemented a high-tech, $3.5-million meter system that accepts cash, credit cards and smartphone payments. The new system has helped generate millions in revenue — $13 million in 2015 alone, 30% more than the year before — but the lawsuit says this money is being made illegally.

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The lawsuit alleges the city is collecting and assessing parking fines at rates higher than those allowed by city ordinance, and, is not letting people take advantage of a discounted $10 early-payment fine for tickets paid within 10 days, as allowed by ordinance. The city is especially hard on repeat offenders, the suit claims, either booting, towing and selling their vehicles, or suspending their driver's licenses if they don't pay.

"Millions of dollars in unlawful and unauthorized fines have been assessed and collected by (Detroit) as a result of their wrongful actions and to the detriment tens of thousands of car owners (if not more) who were assessed excessive fines for alleged parking violations," the lawsuit states.

Among those dinged at the Detroit meter is Grosse Pointe Farms resident Robin Hartnett, who believes the city parking fines are excessive, hurt downtown businesses and the employees who work there like herself.

"Forty-five-dollar tickets – I think – are really mean ... I think it’s way too much," Hartness said. "It's not encouraging people to come downtown Detroit."

Hartnett is currently fighting a $45 expired-meter ticket that she received in September while parked on Madison near the Detroit Athletic Club. She said she was three minutes over the expired time, so she went to fight it. While fighting the ticket, Hartness recalled being behind a Wayne State University student who was fighting $180 in fees for two tickets in one night for being too close to the corner of a driveway.

"She got hammered," Hartnett said."She didn't have $180."

Kristie Bonner of Pleasant Ridge knows the feeling. She went shopping for a $10 "Charlie Brown" Christmas tree in Eastern Market last month and ended up getting a $45 ticket for parking too close to a stop sign.

"Talk about a holiday spoiler," Bonner said. "My tree bargain turned out to be very expensive. There was honestly nothing better to do that to give me a ticket for parking too close to a stop sign?"

As of Tuesday, Bonner had not yet paid the ticket, stating: " I was not exactly ready to dish it out."

The lawsuit takes issue with the actions of former emergency manager Kevyn Orr, who in the spring of 2014 approved higher parking fines — the first in more than 10 years.

Higher fines, new meters raise Detroit parking revenue

Under Orr's order, parking tickets and late fees increased from $30, $50 and $80 to $45, $65 and $95, respectively. Orr's order also eliminated the discounted fine of $10 for those who paid within 10 days of getting a ticket.

The lawsuit claims Orr's proposed order was "never enacted or published and never became the law." But the city has acted as if it did and has been wrongfully charging motorists parking fines inconsistent with Detroit's laws, the lawsuit states.

John Roach, spokesperson for Mayor Mike Duggan, declined comment, citing the law department's policy not to comment on pending litigation.

The plaintiffs are Kayla Friess, 25, of Detroit, who has received numerous parking violations by the city of Detroit over the years. At least one of the tickets was for $45. She paid the fine within 10 days, but was still charged the full amount.

Issa Haddad, 40. of West Bloomfield is the other plaintiff. He also has received numerous parking tickets in Detroit, including at least one for $45.

The lawsuit, filed by attorney Shaun Godwin, is seeking class-action status. The defendants are the city, Wisconsin-based parking meter contractor Duncan Solutions; Detroit parking director Norman White; and James Canty, manager of the city's parking violations bureau.

Attorneys for Duncan Solutions could not be immediately reached for comment.

Expired meter tickets in suburban Detroit range from $20 in Grosse Pointe Park to $10 in Ferndale if paid within 72 hours (it jumps to $25 after that if paid within 10 days of issuance). Ann Arbor charges $10 for a parking ticket if paid by the end of the next business day and $20 if paid within 14 days, while Grand Rapids charges $20 for expired meter tickets in the central city if paid within 10 days, then doubling after that.

Tresa Baldas can be reached at tbaldas@freepress.com. Follow her on Twitter @Tbaldas.