After a particularly deadly 2017 in Des Moines, homicides in Iowa's capital dropped in 2018 by nearly 50 percent.

Slayings in the city declined from 25 in 2017 — the most in the city since 1978 — to 13 in 2018, according to police data. Of the 13 homicides, the attacker is known in 11 cases; four were ruled self-defense, with no arrests made.

Des Moines police ended the year with an 85 percent homicide-clearance rate, compared with 72 percent at the end of 2017.

► Local reporting that matters. Subscribe to the Des Moines Register.

Shootings also dipped from last year's frantic pace. In 2017, police responded to 1,443 calls of possible shots fired, in which officers confirmed gunfire in 265. Police responded to 1,266 calls of shots fired in 2018, confirming 229 shootings.

Police spokesman Sgt. Paul Parizek said the force, in part, attributed the decline to law-enforcement strategies and community awareness. He said the biggest factor in the homicide drop were key arrests made early in the year and during the summer.

Officers keep tabs on repeat offenders and people who, for instance, traffic drugs and weapons. Arresting criminals such as Roman Hellems Jr. — a 23-year-old felon sentenced to eight years in prison after he was found with a stolen gun — can help curb violence as much as arresting a shooter, Parizek said.

Polk County Attorney John Sarcone said he was not sure the decline in homicides could be tied to one cause, saying violent crime can come in cycles.

"It may be that we have some violent people in jail," Sarcone said. "The other side is that there’s good police work going on that's probably prevented things from happening."

Many of the police strategies deployed in 2018 have been used in years past, Parizek said. He commended citizens, not law enforcement tactics, for the decline in fatal domestic fights last year.

“It’s a positive story about the community," Parizek said. "If people out there aren’t shooting and killing each other, that makes our jobs a heck of a lot easier."

A deadly ending to 2018

While there were fewer victims last year, the families of those killed suffered great tragedy.

Those slain included an 8-month-old girl, Raija Straight, who suffered multiple skull fractures, broken ribs and other serious internal injuries. Authorities said the child was killed by her father, Jayden Straight, now charged with murder.

Straight's mother, Ri Bambino, told mourners at a vigil: "Don't let them forget her name."

The first victim of 2018 was Cory Channon, who was fatally shot because the gunman thought he had stolen a weapon from him, police said. At the sentencing of an accomplice in the homicide, who pleaded guilty to lesser charges, some of Channon’s family members echoed a sentiment heard by relatives of others lost to violence.

"Your actions ended his life forever," one woman said. "And it forever changed ours."

The year ended on a particularly violent note when three people were killed in separate stabbings by family members in about a week. Suspects in both incidents were charged within a day.

Joshua Lee Adams, 30, fatally stabbed his mother and his uncle at the home where he lived with his mom on the city’s northeast side days before the year ended, marking the 12th and 13th homicides, authorities said.

Those slayings, investigated into the night as snow fell, came about a week after officers discovered the body of a 50-year-old man who police said was fatally stabbed by his cousin, now charged with murder. His remains were found in an apartment the men shared on the south side — a bloody scene Parizek described as gruesome.

"It was pretty graphic," the sergeant said. "This was not something where anybody inside that home could have not known that something bad had happened."

Authorities have not released a clear motive in either stabbing.

An increase in self-defense homicides

No charges were filed in about a third of the homicides where a shooter or assailant was known because police said several killings were deemed justifiable.

Of the seven justified homicides from 2013 to 2017, officers shot victims in six, according to police data. None of the four in 2018 involved officers.

“People take a little more responsibility for their own safety," Parizek said. "On the flip side of that, we’re seeing more guns involved in (crimes) that are lawfully owned also. It’s a tough balance to strike."

Sarcone said it was too soon to say whether the number of self-defense cases was noteworthy. He doubted there was a discernible trend, he said, because the circumstances of each varied.

Iowa's "stand your ground" law — which since 2017 has allowed law-abiding citizens to not retreat before using deadly force in defense of themselves or others — did not apply to any of 2018's slayings, Parizek said.

In recent years, law enforcement in the metro area has seen an increase in gun-related crimes that include officers seizing firearms from teenagers. But Des Moines detectives hope a new in-house system to analyze and match shell casings to firearms, installed thanks to a federal grant, will assist police in solving gun crimes sooner.

It should be known, Sarcone said, that Polk County law enforcement is on guard.

"This isn’t a place to commit violent crime," Sarcone said. "You're going to be held accountable for it."

The pair of unsolved killings

No one has charged with a crime in the killings of Josue Alonzo Jr., 20, or Tyrese Parson, 17.

Sarcone and Parizek said they believe that, for almost every killing, someone knows something. But that person has not come forward in these slayings.

Alonzo, a new father, was gunned down in April. Police have spoken with several people about his death, but are nearly out of leads.

Parson, a teenager who had participated in the Register's Annual Great Bicycle Ride Across Iowa, was shot in June on the east side, less than a mile from where Alonzo's body was found. Parson had been dead for possibly hours before his body was found on a sidewalk.

Parizek said Parson's peers have not cooperated with officials, but someone he knew came to the station to offer help finding the killer.

The police spokesman said there was reward money at the department for those willing to help authorities solve these crimes. Detectives, Parizek said, need the community's help.

"We’ll put some zeroes on the end of that if you give us information that solves the case.”

A look at each case

Jan. 9: Cory Channon, 39, of Des Moines, was fatally shot after a group of people confronted him at his apartment at 1332 21st St. on the city's northwest side. William Edgar Burton II, 45, shot Channon after he accused him of stealing a gun, police said. Burton, Crystal Raye Purdy, 37, and another man who has not been charged, confronted Channon, prosecutors said. Purdy was sentenced to 35 years in prison after she pleaded guilty to burglary and conspiracy to commit a forcible felony. Initially charged with murder, Purdy agreed to testify against Burton, who police described as her boyfriend. Burton's trial was set for Jan. 28; he also faces charges on accusations he committed an armed robbery in Indianola the day before Channon was killed.

March 7: Christopher John Latimer, 34,died from injuries he suffered while fighting his roommate at their apartment at 1076 21st St. The Des Moines man, who lived with his mother and her boyfriend, had been fighting with the boyfriend for hours. After police responded at 1 a.m. to a neighbor's call, Latimer's mother, Lynne Marie Bailey, was arrested on an unrelated warrant for marijuana possession. By 6 a.m., the fighting resumed, police were called, and Latimer was dead. Officials detained Bailey's boyfriend, who said he was defending himself against Latimer. An autopsy showed Latimer's cause of death was manual compression of the neck. No charges were filed.

April 27: Josue D. Alonzo Jr. of Des Moines was fatally shot at about 10:20 p.m. at East 30th Street and Garfield Avenue. The 20-year-old was pronounced dead at the scene. Alonzo was a newlywed and recent high school graduate with an infant daughter, his family said. No arrests have been made and police said there were no strong suspect leads, but shortly after Alonzo died, authorities asked for the public's help in finding a red, four-door compact car in connection to the shooting.

June 3: Jerry Goff, 40, died at Iowa Methodist Medical Center after being shot on the city's west side. Investigators believe the Des Moines man was fighting with family members at 38th Street and Woodland Avenue before the shooting. Two days after the shooting, Polk County Attorney John Sarcone said the fatality was a "clear case of self-defense." No charges were filed and the shooter was not identified by authorities.

June 8: Tyrese Robert Parson, 17, of Des Moines was dead for hours when his body was found about 6:30 p.m. in the 800 block of East 27th Street. Police said he suffered a gunshot wound. No suspect information was released and no arrests have been made.

July 11: Amund Benjamin Haarstad, of Fergus Falls, Minnesota, was killed while trying to burglarize a south-side muffler shop, officials said. Police responded at 7:15 a.m. to 1400 Army Post Road for a call of a burglary and found Haarstad's body. Police believe Haarstad was loading items from the shop into a pickup he had stolen in a different state. The business' owner, Thomas Kraft, caught him mid-act and a confrontation ensued. Haarstad, who was unarmed, was killed by a ricochet, authorities said. No charges were filed.

July 14: Raija Straight, 8 months old, was beaten to death by her father, Jayden, police said. The Des Moines child arrived July 13 at Mercy Medical Center with a fractured skull, a ruptured spleen and broken ribs. She cried profusely until she went unconscious, court records show, and died the next day. Jayden, who was the only one near the baby before she was taken to the hospital, has been charged with first-degree murder and child endangerment resulting in death. The 18-year-old man's trial was set for May 13.

Aug. 11: Joshua James Wheeler, 32, of Des Moines was shot after entering the home of his former girlfriend in 200 block of East Park Avenue, police said. At about 11:30 p.m., the woman and a male friend were in the house, as well as two children, one of whom was Wheeler's. Wheeler, violating a no-contact order, drove to the home and the three began arguing outside. Wheeler followed the two into the house and began assaulting the man, authorities said. He warned Wheeler he was armed and told him to leave, but the fighting continued and Wheeler was shot in the abdomen. Authorities called it a case of self-defense and no charges were filed.

Sept. 30: Aaron Ross, 28, of Des Moines, died after he was shot in broad daylight in the 1200 block of East 13th Street. Ross was sitting in a car about 1:15 p.m. that day with his girlfriend and two of his children when a man approached and fired multiple shots, striking Ross.Tyrone Hughes Jr., 28, of Chicago was charged with first-degree murder. Police said Hughes' wallet was recovered near the crime scene. Hughes' arraignment was set for Feb. 1.

Oct. 4: Thurmon Cole, 42, was killed during a robbery at his north-side apartment. Police said Cornelius Davis, 31, went to Cole's apartment at 2411 Welbeck Road just after 2 a.m. He attempted to rob Cole, who was in the apartment with his girlfriend. A struggle ensued and Cole was shot. The father of five died of his injuries, while his girlfriend suffered a black eye, cuts and bruises. Davis faces charges of first-degree murder, first-degree robbery and willful injury causing serious injury. Davis had been convicted in a Minnesota stabbing in 2006. His murder trial was set for Feb. 25.

Dec. 19: Police discovered the body of 50-year-old Albert Barron III, who had been fatally stabbed, in his south-side apartment while conducting a welfare check. His cousin, Sean Michael Foster, 30, was charged with first-degree murder. Barron may have been dead for days before his remains were found; detectives believe Foster stabbed him and left the body in the apartment they shared at 2454 Indianola Ave. Officers found Foster asleep at 4 p.m. when they discovered the bloody crime scene, police said.

Dec. 28: Tracy Linn Adams, 49, and Gaylord George Jolly, Jr., 45, were found stabbed to death inside a home at 3927 E. 26th St. on the city’s northeast side. Police charged 30-year-old Joshua Lee Adams — Tracy Adams’ son and Jolly’s nephew — with two counts of first-degree murder. His bond was set at $2 million cash.