The National Law Enforcement Museum in Washington, D.C., opened its doors to the public this weekend following nearly three decades of work to make the dream a reality.

The 57,000-square-foot, $103 million museum is located in the downtown Judiciary Square neighborhood, between the National Law Enforcement Officers Memorial and District of Columbia Courthouse. Walking past the venue, one might not realize there's even a museum there. The three-story building has a ground-level entrance and exit, both of which are enclosed in large glass rooms, but the rest of the museum remains out of sight.

All of the exhibits are located on the lowest of the three underground levels; the other two hold a gift shop, donor wall, and balcony overlooking the bottom floor. Visitors can learn about the 400-year history of law enforcement in America, see pieces of evidence from famous cases, discover how crime scenes are investigated by forensic experts, and pay tribute to recently fallen officers.

The museum’s history dates back to 1989, when national law enforcement officials came up with the idea of creating a central space to teach people visiting America’s capital about the history of police. The first part of that project was creating a memorial to honor slain police officers, which was unveiled in 1991. But it wasn’t until November 2000 when Congress and then-President Bill Clinton approved the museum’s construction on federal land, which was then followed by a five-year public review process.

In 2010, project leaders for the privately funded facility broke ground on the Motorola Solutions Foundation Building. They had expected a three-year construction and design process. However, constrains, including the recession, pushed that to an eight-year process, according to Robyn Small, a museum spokeswoman.

Had the museum been built two decades ago, it would have given visitors a very different experience than the one curators sought to give them in 2018. “The museum has two core missions. One is to tell the history of American law enforcement. The other is to help strengthen the relationship with citizens and the communities that the law enforcement serve,” Small said during a recent tour of the facility.

Items on display from local crime events include U.S. Park Police helicopter “Eagle One,” which was used to rescue five people from the iced-over Potomac River in Washington when Air Florida Flight 90 crashed into the 14th Street Bridge and sunk in the frigid waters on Jan. 13, 1982.

The rifle used in the infamous "D.C. sniper" shootings in 2002 is another one of the 7,000 items on site for visitors to see. When asked if families of the 17 people killed during the murdering spree were offended or upset about the gun being on display, Small said she was not aware of any complaints.

“No, not that I’m aware of,” Small said. "All of our collection comes from Prince William County for the sniper. They gave us all of the evidence in the case."

Nonlocal items include a red desk phone that sits near the entrance in the main room. It was the first phone to ever receive a 911 call in 1968 and is on loan from Haleyville, Ala., where the call was placed.

The bulletproof vest that gangster Al Capone wore and the desk that belonged to the FBI’s first-ever director, J. Edgar Hoover, are also housed in the museum. An additional 14,000 items are located off-site and will be switched out with current exhibits in the coming months and years.

A “Reel to Real” theater and exhibit rooms show how members of this profession have been portrayed in famous movies, TV shows, and books, then explains how law enforcement would have actually handled that situation. An adjacent pop culture room holds a suit from the "RoboCop" movies, Jack Bauer’s sweatshirt from “24,” and dozens of other items.

The space is filled with vehicles for people to sit in and snap a selfie, as well as firearms, though those are locked up behind glass.

The oldest item on display is a sheriff’s writ from 1703, which can be found in the central hall, where a timeline shows the evolution of policing. In the 17th, 18th, and 19th centuries, officers in the Deep South were largely responsible for going after runaway slaves, while up north in the New England area, law enforcement was more of a neighborhood watch initiative.

“They're very candid about the problems in the community between citizens and law enforcement and the need to change,” Small said about the curators' work. “We feel very fortunate. This museum couldn’t have come at a better time.”

Small said the museum can handle about 500 visitors an hour and the first few hours of its grand opening day had been sold out. Outside the facility, a police band entertained guests.

Free face painting and snacks were available to non-museum guests outside as part of the opening festivities. Two lines of old-fashioned police cars were on display in the street, including a 1972 Plymouth Fury pursuit vehicle from Prince William County.

One of the goals of the National Law Enforcement Officer Memorial Fund, which created the initiative for the museum, was to give visitors the chance to "walk in the shoes” of the country’s 900,000 law enforcement officers, including sheriff’s departments, game wardens, transit officers, patrol cops, and detectives.

The “Take the Case” exhibit gives visitors the chance to analyze evidence, carry out autopsies, and look at bullet and fingerprint forensic evidence, then determine if they have enough relevant evidence to solve a crime. The evidence is all from real cases.

The interactive space includes a small theater room where people can watch an interrogation take place. The museum curator purposely constructed the room to feel and look exactly like a questioning room inside a police station. It features a scent diffuser to make the room smell musky, Small said.

The “Witness to History" program allows visitors to get a firsthand account of significant historical events from those who were there as well as analysis from leaders in law enforcement through interactive screens.

A nearly 3,000-square-foot room features the “Five Communities” exhibit, where visitors can learn about grassroots efforts to improve police and community relations in five cities in America. The current ones being featured are Cleveland, Ohio; Dallas; Chicago; Somerville, Mass.; and Charleston, S.C.

Before leaving, visitors are able to pay their respects to the approximately 700 recently fallen law enforcement officers whose names and photos are on display in a private room off the main hall. Nearly 19,000 federal, state, and local officers in the U.S. have died since the first documented line of duty death in 1792, including 108 in 2017. In 2018, there have been 110 law enforcement officer fatalities, according to the National Law Enforcement Officer Memorial Fund.

The museum also contains large private rooms for classroom and group events. It plans to sponsor both adult and kid-friendly events starting this month. Later this month, the museum is holding the first “Brewsday” event for adults 21 years of age and older to learn about law enforcement’s portrayal in pop culture through recent decades.

In November, it will host a panel discussion on the opioid crisis in America.

The museum is located at 444 E Street NW and the price of admission is $21.95 for adults.