In law enforcement, as in most every other profession, there are good ones and bad ones, but what most people seem to remember are the really bad ones.

Manuel Pardo, a former Florida police officer turned serial killer who was executed Tuesday, was one of the latter, officials say. He shot nine people to death in the late 1980s, claiming he was a ”soldier” ridding the streets of the wicked.

Most of Pardo's victims were reportedly involved with drugs, and Pardo claimed he was doing society a favor by ridding the streets of low-lifes who “have no right to live.” Authorities say he was a cold-blooded serial killer; one retired detective described him as “Ted Bundy-esque," while a retired prosecutor called him “very cold.”

Michael Tabman, a former Fairfax County, Va., police officer and former FBI agent, said law enforcement agencies have better screening tools these days to weed out potential problem applicants, "but we haven't perfected predicting behavior."

'Death Row Romeo' faces execution in Florida

He said people attracted to police work often have personalities that are "machismo-oriented" and "comfortable with a lot of authority," among other traits.

"A lot of that is a type of personality that in a perfect storm … can morph into anti-social behavior," said Tabman, an author who also blogs about crime and security. 

Herewith are some other notorious cases involving cops gone bad:

M. Spencer Green / AP file

Former Bolingbrook, Ill., police Sgt. Drew Peterson arrives at the Will County Courthouse in Joliet, Ill., for his arraignment on charges of first-degree murder on May 8, 2009.

Drew Peterson
The former Bolingbrook, Ill., police sergeant was convicted in September of murdering his third wife, Kathleen Savio, who was found dead in her bathtub in 2004. Authorities presume his fourth wife, Stacy Peterson, who vanished in 2007, is also dead; Peterson is a suspect but has never been charged in that case.

Before his 2009 arrest, according to media reports, Peterson seemed to taunt authorities, joking on talk shows and even suggesting a "Win a Date With Drew" contest.

After his conviction, Savio’s family members said justice was finally served. "Game over, Drew," Stacy Peterson's sister, Cassandra Cales, said. "He can wipe the smirk off his face. It's time to pay." 

Via KTLA / AP file

A frame from a video shot by George Holliday from his apartment in a suburb of Los Angeles shows a group of police officers beating Rodney King as other officers watch on March 31, 1991.

Rodney King beating
It was perhaps the most famous of all homemade videos – the 1991 clip of Los Angeles police officers beating black motorist Rodney King following a car chase.

A year later, a California jury acquitted three officers and deadlocked on charges for a fourth. The verdict sparked violent race riots in Los Angeles, and by the time order was restored, more than 50 people had died.

A federal jury later convicted two of the police officers, Stacey Koon and Laurence Powell, of a federal charge of violating King’s civil rights and sentenced them to 30 months in prison.

King died in June at age 47.

Katrina bridge shootings
In the chaos after Hurricane Katrina, six unarmed civilians were shot – two of them fatally – on the Danziger Bridge in New Orleans on Sept. 4, 2005. One of the dead, Ronald Madison, was a 40-year-old mentally disabled man who was shot in the back. Police claimed they opened fire because they thought people were shooting at them from the base of the bridge.

Getty Images file

Cars pass over the Danziger Bridge July 14, 2010 in New Orleans.

In August 2011, four former New Orleans police officers -- Kenneth Bowen, Robert Gisevius, Anthony Villavaso and Robert Faulcon – were convicted of civil-rights violations and firearms and other charges in the shootings. A fifth former officer, Arthur "Archie" Kaufman, who was assigned to investigate the shootings, was convicted of helping to orchestrate a cover-up.

“The officers who shot innocent people on the bridge and then went to great lengths to cover up their own crimes have finally been held accountable for their actions,” Thomas E. Perez, assistant attorney general for the Justice Department’s civil rights division, said when the men were sentenced to long prison terms in April.

Reuters file

Former New York City police officer Justin Volpe in 1997.

Abner Louima beating
Louima, a Haitian immigrant, was brutally beaten and sodomized with the handle of a toilet plunger in the bathroom of the 70th Precinct station house in Brooklyn, N.Y., after being arrested outside a night club in August 1997.

One cop, Justin Volpe, was sentenced in 1999 to 30 years in prison for what the judge called an “unusually heinous” crime and a “barbarous misuse of power.” Another, Charles Schwartz, who was initially accused of holding Louima down, pleaded guilty to perjury and was given a five-year sentence. Two other officers who were indicted for allegedly trying to cover up the assault had their convictions reversed due to insufficient evidence.

Chicago Sun-Times / AP

Former Chicago police officer Jon Burge, convicted of lying about the torture of suspects, walks to his attorneys' office following the first day of his sentencing hearing at the federal building in Chicago on Jan. 20, 2011.

Louima sued New York City and its main police union and won a $8.75 million settlement.

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Jon Burge
Burge was a former Chicago Police Department detective and commander who, along with the “Midnight Crew” of officers under his command, allegedly beat and tortured criminal suspects in the 1970s and '80s in order to gain confessions. Victims said they were burned with cigarette butts, smothered with plastic bags, shocked in the genitals and forced to play Russian roulette with a .44-caliber gun.

Although Burge was protected by the statute of limitations on the claims of abuse, he was convicted of lying about the torture. He was sentenced in January 2011 to 4 ½ years in prison.

The city agreed to pay more than $7 million to settle two torture lawsuits involving Burge.

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Gerald Herbert / AP

This flood wall and floodgate are along Lakeshore Drive and Lake Pontchartrain in New Orleans, La.

In the busy and under-staffed offices of New Orleans' flood-control leaders, there's an uneasy feeling about what lies ahead.

By the time the next hurricane season starts in June of 2013, the city will take control of much of a revamped protection system of gates, walls and armored levees that the Army Corps of Engineers has spent about $12 billion building. The corps has about $1 billion worth of work left. 

Engineers consider it a Rolls Royce of flood protection — comparable to systems in seaside European cities such as St. Petersburg, Venice, Rotterdam and Amsterdam. Whether the infrastructure can hold is less in question than whether New Orleans can be trusted with the keys. 

The Army Corps estimates it will take $38 million a year to pay for upkeep, maintenance and operational costs after it's turned over to local officials. 

Local flood-control chief Robert Turner said he has questions about where that money will come from. At current funding levels, the region will run out of money to properly operate the high-powered system within a decade unless a new revenue source is found. 

"There's a price to pay for resiliency," the levee engineer said from his office at the Southeast Louisiana Flood Protection Authority-East. "We can't let pieces of this system die away. We can't be parochial about it." 

On Nov. 6, New Orleans voters were faced with one of their first challenges on flood protection when they voted on renewal of a critical levee tax. The tax levy was approved, meaning millions of dollars should be available annually for levee maintenance. 

Bob Bea, a civil engineer at the University of California, said the region must find additional money to keep the system working properly. "If you try to operate it and maintain it on a shoestring, then it won't provide the protection that people deserve." 

Many locals remain uneasy, even though Turner's agency is a welcome replacement for local levee boards that were previously derided. 

"It's scary," said C. Ray Bergeron, owner of Fleur De Lis Car Care, a service station in the Lakeview neighborhood where water rose to rooftops after levees collapsed during Hurricane Katrina in August 2005. Before Katrina, Bergeron said the local levee boards were complacent. "They told everybody everything was fine, 'Oh yeah, it's fine. Let's go have martinis and lunch.'" 

After Katrina, the locally run levee boards that oversaw the area's defenses were vilified, and quickly replaced by the regional levee district run by Turner. 

Congressional investigations found the old Orleans Levee Board more interested in managing a casino license and two marinas than looking after levees. Inspections were ceremonial, millions of dollars were spent on a fountain and overpasses rather than on levee protection. And there was confusion over who was responsible for managing the fragmented levee system, U.S. Senate investigations revealed. 

Still, experts generally agree the old levee board's failings did not cause the levees to collapse during Katrina. Poor levee designs by the corps and the sheer strength of Katrina get the lion's share of the blame. 

Since the Flood Control Act of 1936, the Army Corps has given local or state authorities oversight of water-control projects, whether earthen levees in the Midwest or beach walls in New England. 

Bill Haber / AP

Water is pumped through giant tubes around the floodgate at the London Ave. outflow canal during a test in New Orleans in May 2009.

"That's been the eternal problem with flood-protection systems," said Thomas Wolff, an engineer at Michigan State University. "You build something very good and then give it to local interests who are not as well-funded." 

New Orleans is an unusual case because the area is inheriting the nation's first-of-its-kind urban flood control system. 

"We've given a very expensive system to a place that may not be able to afford it over the long term," said Leonard Shabman, an Arlington, Va.-based water resources expert. Letting the Army Corps run it isn't much of a solution either, he added. "It's not like the corps' budget is flush." 

The nation has spent lavishly on fixing the system in the seven years since Katrina flooded 80 percent of New Orleans and left 1,800 people dead. 

"It is better than what the Dutch have for the types of storms we have," said Carlton Dufrechou, a member of the board of the Lake Pontchartrain Basin Foundation, which monitors local environmental issues. 

Ensuring it remains that way could be tricky. The biggest headaches are several mega-projects with lots of moving parts, all needing constant upkeep. The corps is building them across major waterways that lead into New Orleans. 

Take for instance the 1.8-mile-long, 26-foot-high surge barrier southeast of the French Quarter that blocks water coming up from the Gulf of Mexico across lakes and into the city's canals. Water from this direction doomed the Lower 9th Ward and threatened to flood the French Quarter. Maintaining this giant wall alone will cost $4 million or more a year. 

"You have to get out there and do exercises, do the preventive maintenance, change out equipment over time on a particular schedule," Turner said, enumerating the challenges. "There are a lot of cases where a single thing goes wrong and that can create a failure, a complete failure where you can't close the system." 

There is a mounting list of to-dos. 

Already, lightning has knocked out chunks of wall. Grass hasn't grown well on several new stretches of levee. Louisiana State University grass experts have been called in to help seed them. 

There are recurring problems with vibrations and shuddering on a new floodgate at Bayou Dupre in St. Bernard Parish. The corps has plans to overhaul the structure in the spring before handing it over to local control. And there will be the inevitable sinking of levees and structures, as always happens in south Louisiana's naturally soft soils. Over time, levees will have to be raised. 

Col. Ed Fleming, the New Orleans corps commander, said his outfit will work to ensure the transition to local control is smooth. 

"This happens with corps civil projects all over the country. That's the way it works in Iraq, Afghanistan," he said. "We have authority to build, but we have no authority to do operations and maintenance." 

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As Isaac lingered outside her door, Connie Uddo was busy Wednesday calling elderly friends in her neighborhood to make sure they were holding up. She, like the majority of New Orleans residents, had no power.

Kate Snow / NBC News

Connie Uddo on Thursday, Aug. 30, stands at the non-profit center she started after Katrina.

“It’s just a tedious, long, arduous storm,” she said.

Storms are a big part of life in New Orleans. They always have been. There are records of hurricanes hitting the Crescent City as far back as the 1700s.

But things changed when Hurricane Katrina struck seven years ago — especially for Uddo.

“Our neighborhood, it was condemned, uninhabitable and unsafe. You had to have a pass to get in,” she said.

That is something she never wants to live through again — she doesn’t think she could handle it. As Isaac was bearing down, she felt a familiar mixture of dread and anxiety.

“The wind had me a little freaked out at points last night because our house was shaking a lot and the windows were rattling,” she said.

Related: Isaac loses steam, but brings flooding, power outages
Related: 'They were screaming away': Louisiana man recounts rescue 

Uddo and her kids had evacuated just before Katrina hit. In October of 2005, when she returned to her 90-year-old wood and plaster home, she found a mold-infested mess. The first floor, which they had renovated as rental units, had been under eight feet of water, which took a month to drain out. 

Slideshow: Isaac moves inland

A downgraded Isaac floods coastal communities and forces new evacuations, but levees still hold.

Launch slideshow

“It was horrific. It was shocking. It was something that I never thought I would ever see in my lifetime ... everything was gray.," she said. "It literally looked like a nuclear disaster. There were no birds, insects, squirrels. The silence was just deafening.”

Uddo thought about leaving for good. She cried — a lot.

“It wasn’t just the physical loss,” she said. “It was the emotional loss of your community, your social network, your children’s friends.”

But Uddo decided to move back and rebuild. In January 2006, her family was the first of 10 families in her neighborhood to have electricity.

Lakeview, she said, was a “green dot” on a city planning map — a place that some planners thought would become nothing but green space with no residential homes. 

She wouldn't hear of it. "We’re a hundred-year-old neighborhood. You don’t tell a hundred-year-old neighborhood that."

So she rebuilt, and she convinced others to do the same. Uddo would walk around the neighborhood asking plumbers, roofers, builders and other tradespeople for their phone numbers. Since phone books no longer worked, she compiled a list. She counseled her neighbors at her dining room table. She recruited teen-aged volunteers to come to the neighborhood and clean up the front yards so that returning residents wouldn't be as shocked as she had been when she first drove in.

Eventually, Uddo opened St. Paul’s Homecoming Center, which still operates and helps residents who fled Katrina. The center has coordinated more than 50,000 volunteers.

As soon as Isaac lets up enough, probably on Thursday, Uddo plans to go back to the Center and start the cleanup. So far, she hasn’t seen any major flooding in her neighborhood. On a walk earlier Wednesday she checked on the trees she recently planted. They’re tattered, but still standing. The elderly neighbors she called are doing all right too. And for that, she’s thankful.

“Hopefully tomorrow we’ll be back in action,” she said.

Wednesday was spent napping, having tea, catching up on laundry and house chores.

“I really feel blessed. I don’t want to jinx it. It’s not over. But it could’ve been worse.  So many things could’ve happened.”

Uddo thinks a storm like Isaac solidifies her community.

“Once again we’re a stronger, more unified community because of it. And that’s the silver lining. You come out stronger."

One of the biggest lessons of Katrina, Uddo said, is that neighbors have to look out for each other. Before Katrina, they never would have coordinated before a storm. On Tuesday night, before the power went out, Uddo and her husband went up the block for a neighborhood gathering. They made plans together about what they would do if the water rose on their streets.

“At the end of the day, all we have is each other,” she said.

To contact Uddo's organization, St. Paul's Homecoming Center, please visit their website, or call: 504-644-4125.

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Mario Tama / Getty Images file

The Danziger Bridge in New Orleans was the site of a deadly shooting of unarmed civilians by police officers in the aftermath of Hurricane Katrina

Five former New Orleans police officers were sentenced to long prison terms Wednesday for their roles in the shootings at a bridge that left two civilians dead and four others wounded in the chaotic aftermath of Hurricane Katrina.

A federal judge sentenced four of the officers convicted of participating in the shootings to terms ranging from 38 years to 65 years, according to local media reports. The fifth officer received six years for covering up the killings.

U.S. District Judge Kurt Engelhardt called it “a sad day for New Orleans” and also criticized the plea bargains that other officers got in exchange for cooperating with the government, NOLA.com reported.

"Using liars to convict liars is no way to pursue justice," Engelhardt said, according to NOLA.com.

The Justice Department hailed the lengthy sentences in a case that shed a national spotlight on New Orleans police corruption as testament that “no one is above the law."

“We hope that today’s sentences give a measure of peace and closure to the victims of this terrible shooting, who have suffered unspeakable pain and who have waited so patiently for justice to be done,” Thomas E. Perez, assistant attorney general for the Justice Department’s civil rights division, said in a statement. “The officers who shot innocent people on the bridge and then went to great lengths to cover up their own crimes have finally been held accountable for their actions. As a result of today’s sentencing, the city of New Orleans can take another step forward.”

Kenneth Bowen, 38; Robert Gisevius, 39; Anthony Villavaso, 35; and Robert Faulcon, 48, were convicted in August of civil-rights violations and firearms and other charges in the shootings, according to The Associated Press. Retired Sgt. Arthur "Archie" Kaufman, who was assigned to investigate the shootings, was convicted of helping orchestrate the cover-up.

Faulcon received the stiffest sentence, 65 years. Bowen and Gisevius each got 40 years, and Villavaso got 38 years. Kaufman got the lightest sentence, six years.

Sean Gardner / Reuters

Sherrel Johnson, mother of James Brissette Jr., who was killed on the Danziger Bridge, is hugged by Rev. Aubrey Johnson after the sentencing of former New Orleans police officers on Wednesday.

Bowen, Gisevius, Villavaso and Faulcon were among about a dozen officers who responded to a radio call that someone was shooting at police near the Danziger Bridge in east New Orleans on Sept. 4, 2005. That was less than a week after Katrina made landfall, swamping a good part of the city and leading to televised scenes of looting and lawlessness in some neighborhoods.

Witnesses testified that the officers jumped out of a truck and fired with AK-47s and shotguns at unarmed civilians walking on the bridge.

The officers later claimed they shot only after being threatened or fired on and that they had seen weapons in the victims' hands.

Prosecutors said the people on the bridge were families seeking food.

Read local coverage on WDSU.com

A New Orleans couple, their daughter and their nephew were among those wounded, and a family friend, James Brissette, 17, was killed.  He was shot in the back, the leg, both arms and the back of the head, and died on the bridge, according to the Justice Department.

At a second shooting a few minutes later on the west side of the bridge, Ronald Madison, a 40-year-old man with severe mental and physical disabilities, was shot  in the back while running away. He died near the base of the bridge. 

Kaufman, the lead investigator in the case, retired from the force in May 2011. He planted a gun at the scene and helped falsify official reports of the shootings, according to media reports.

The sentencing came after a morning of testimony from victims of the shootings as well as family members and friends of the former police officers.

Lance Madison told the court his brother Ronald was "gunned down and killed without mercy" by police that day, NOLA.com reported.

Madison told the five former officers: "You are the reason I can no longer trust law enforcement," according to NOLA.com.

Five other former NOPD officers who pleaded guilty before trial, admitting that they had participated in a conspiracy to obstruct justice and cover-up, were all sentenced previously. They got prison terms ranging from three years to eight years.

Information from NOLA.com., WDSU.com and The Associated Press is included in this report.

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