A volunteer helps prepare the hair of a Pakistani bride before a mass marriage ceremony in Karachi on March 25. (Asif Hassan/AFP/Getty Images)

When families book a wedding at the Envoy Continental Hotel in Islamabad, they hope the occasion will be memorable because of the beautiful bride, the impressive venue with its marble spiral staircase and crystal chandeliers, and a delicious dinner.

But these days, if the party doesn’t shut down by 10 p.m., the police might make an unwelcome appearance — and the proud parents of the bride and groom could end the evening behind bars, creating an unforgettable memory, just not the sort they had intended.

Talk about wedding crashers.

The city district administration recently warned that if marriage halls do not close before the 10 p.m. deadline, parents of the bride and groom risk arrest.

The drastic measure is the latest move to enforce a city ordinance regulating marriage ceremonies in an effort to address Pakistan’s energy shortages.

A crackdown is also underway in the capital’s twin city of Rawalpindi — not just aimed at enforcing the curfew, but also enforcing the so-called one-dish rule, which limits the number of courses served during the traditionally lavish celebrations to just one.

Each region in Pakistan can implement its own version of the Punjab Marriage Functions Act, which is intended to stop the wasting of food and reduce social pressure on poor people who cannot afford splashy weddings.

Last month, a Rawalpindi official was quoted in the News, a major newspaper, as saying: “Violations of the Marriage Act will not be allowed and no relaxation will be given to anyone.”

The ordinance has been the subject of complaints in other cities, as well. In Lahore, a marriage hall association challenged the government, claiming there is no legal foundation for the law and petitioning the Lahore High Court to allow their businesses to remain open until midnight.

Pakistan has been struggling with an energy crisis that has left the country burdened by rolling blackouts and natural gas rationing.

Initially, the government tasked marriage-hall owners with enforcing the ban, but the owners continued to allow post-10 p.m. festivities anyway. The threat of fines and citations — and even arrest — puts additional pressure on the parents of the brides and grooms.

The early closure rule is nothing new, said Muhammad Yusuf, general manager of the Envoy Continental Hotel. It started years ago, and although it was mostly ignored, infractions were sometimes punished with fines. But enforcement through the threatened arrest of parents is a recent development.

“It will affect business, and the situation is already bad,” Yusuf said.

Hotels are frequent venues for big wedding receptions. The hotel industry in Islamabad suffered after the Marriott Hotel, one of the largest and most exclusive in the capital, was the target of suicide bombers in 2008. The Marriott was rebuilt and reopened three months later with improved security.

“Business has not come back” since 2008, Yusuf said. “Foreigners are not coming to Pakistan, and so many hotels are already closed. Every year we go back and back. Every year it gets worse.”

“Dinner starts at 8, and during marriages it goes until 12,” he added. “This will cause losses for hotels. The reason is people don’t come to marriages at 8. They come at 9 and they leave at 11 or 12 o’clock. Everyone is upset about this.”

The one-dish rule also has its staunch opponents.

“Why would you want to stop people from serving food at weddings? Food served at weddings is both produced and prepared locally,” Feisal H. Naqvi, a Lahore-based lawyer, wrote in a recent column in the Express Tribune newspaper. “Banning or limiting food at weddings is, therefore, the same as banning or limiting local businesses. Why on God’s green earth would anyone ever do that?”