The Robison family murders (also known as the Good Hart murders) are an unsolved mass murder which occurred in the secluded resort area of Good Hart, Michigan, on June 25, 1968. The victims were a vacationing upper-middle-class family from Lathrup Village who were shot and killed inside their Lake Michigan holiday cottage, with two decedents also bludgeoned with a hammer prior to death. Their bodies remained undiscovered until July 22.

Following an exhaustive investigation by the Michigan State Police and the Emmet County Sheriff's Office, initial investigations were completed in December 1969, with ample circumstantial evidence indicating the perpetrator was a senior employee of Richard Robison's named Joseph Raymond Scolaro III, who had engaged in embezzlement which his employer is known to have discovered and begun investigating shortly before his murder.

Emmett County prosecutors initially determined insufficient evidence existed to successfully prosecute Scolaro, who committed suicide in March 1973 at age 34—reportedly upon hearing of his likely impending indictment for the murders following the reopening of the case and discovery of further physical evidence attesting to his guilt. He remains the sole and prime suspect in the murders.

At the time of their commission and discovery, the Robison family murders were considered the worst case of mass murder in Michigan history. Officially, the case remains open.

Robison family Richard Carl Robison was born in Wayne County, Michigan, in November 1925. He had met his fiancée, Shirley Fulton, in the mid-1940s while both attended college. The couple wed in 1947 and had four children: Richard Jr. (b. 1948); Gary (b. 1951); Randall (b. 1955); and Susan (b. 1960).

Robison had founded and operated a small advertisement agency named R. C. Robison & Associates in the mid-1950s. The firm strategized advertisement campaigns for businesses within the Detroit region; he also worked as a commercial artist, executive and publisher for Impresario magazine, which focused on cultural issues such as the arts, theatricals and music and was also based within his one-story Southfield office. The markedly wealthy family owned a private Learjet, and lived in the affluent Detroit suburb of Lathrup Village.

By 1968, Richard Jr. attended Eastern Michigan University, Gary was a student at Southfield-Lathrup High School, Randall was a middle school student, and Susan—described as a "pony mad" child—a first grade student. The family regularly attended church services, and neither parent drank, smoked or gambled.

Vacation In the summer of 1968, the Robisons embarked on their annual vacation to the Blisswood Resort community within the small town of Good Hart. The family planned to spend three weeks of their vacation at Summerset, the seasonal log-and-stone holiday cottage they had purchased in the 1950s for $15,000. The five-room cottage itself was situated at the end of a long private driveway within a heavily-wooded area and which at one section runs alongside a 100-foot bluff close to the Lake Michigan shoreline. The family had visited the property every summer since 1957.

The vacation began on Sunday, June 16, with the family traveling in two cars to the destination. They were accompanied by several traveling companions, who would stay in their own rented holiday homes. These individuals included friends of the Robison boys, some business acquaintances, and personal friends of Richard Sr. and Shirley. Among those to know about the vacation and the location of the Robisons' secluded holiday home were several senior employees of Impresario magazine.

On June 23, one of the Robisons' traveling companions, 18-year-old Norman James Bliss (the son of the caretaker of Blisswood Resort and a close friend of Richard Jr.), was killed in a motorcycling accident while returning to Good Hart from nearby Cross Village, reportedly while intoxicated. An autopsy revealed his cause of death to be cerebral hemorrhage. The accident occurred sometime after 1:30 a.m., and the Robison family did not learn of the accident until that evening. Upon receipt of this news, Richard Sr. paid personal condolences to Bliss's parents at their Good Hart holiday home, offering to pay for the teenager's grave marker and flowers or a wreath. He also explained the family would be unable to attend the funeral as they were due to fly from Pellston Regional Airport to Kentucky, then Florida, with view to purchasing real estate and would "not be back [to their cottage] for a couple of weeks." He added the earliest date they would likely return would be July 15.

June 25, 1968 On the morning of June 25, Richard Robison Sr. telephoned his personal banker at the National Bank of Detroit, Frank Joity, to discuss business pertaining to an expected recent deposit to his account of $200,000, only to be informed that the deposit had not been made, of financial irregularities within his business account within recent weeks, and that his current business balance was just $15,000. These revelations infuriated Robison, who telephoned his receptionist, demanding to speak to a senior employee of his named Joseph Scolaro III—the only employee of his with direct access to company accounts—to seek an explanation as to the missing funds. Investigators later determined this phone call had been made shortly after 10:30 a.m. Telephone records would later determine that over the following hours, Robison Sr. both called and attempted to call Scolaro on seventeen occasions, demanding an explanation.

Due to the conversation Robison Sr. had with the caretaker of Blisswood Resort the previous evening pertaining to impending travel plans, neither the Robisons' travel companions nor the caretakers of the resort became suspicious when the family were not seen for several weeks despite the fact the family's Ford LTD station wagon plus their rented Chrysler Newport remained parked close to the cottage. This was in part due to the fact that, in previous years, the family had largely, though not exclusively, kept to themselves during their vacations at the resort.

The final confirmed sighting of the Robisons occurred at approximately 4:30 p.m. on June 25, when two individuals tasked to trim trees within the grounds of Summerset left the property.

Murders Investigators would later determine the most likely time the Robison family were murdered was in the early evening of June 25, 1968. The murders evidently began when the assailant was outside the property, as five .22-caliber semi-automatic rifle gunshots were fired through a rear window of Summerset Cottage at Richard Robison Sr. as he sat in a chair. The perpetrator then entered the cottage through an unlocked door and killed the remaining five family members—Shirley (40), Richard Jr. (19), Gary (16), Randall (12), and Susan (7)—with shots to the head and body from both the rifle and a .25-caliber semi-automatic pistol. Most likely, the final two family members killed were Richard Jr. and Gary, who were likely shot as they attempted to retrieve a rifle the family stored in a closet in the rear bedroom. Susan and Richard Sr. were also bludgeoned with a claw hammer found at the murder scene, although there were few signs of a struggle within the cottage.

A single bloody footprint on the floor would lead investigators to conclude that one person had committed the murders, and this individual had most likely closed all the curtains to the cottage and crudely attempted to cover the bullet holes in the window from his initial salvo with a piece of cardboard before turning on the heating within the property, then locking the door to the premises before leaving the scene. Fifteen spent shell casings—eleven .22-caliber and four .25-caliber—were left at the premises. A note penned upon a section of paper towel affixed to the cottage door read 'Be back by 7-10. Robison.'

Discovery The bodies of the Robison family remained undiscovered until July 22. Their bodies were found by the owner and caretaker of the resort, Chauncey Bliss, following a complaint from a neighbor of the family of a pungent odor emanating from the cottage she had noted while playing a card game with friends on the grounds of her own property some from the Robison cottage that afternoon. Bliss found both doors to the property locked; he pried open the molding to gain entry to the cottage only to discover the crime scene. Bliss immediately notified authorities.

Investigators would determine Richard Sr. had been shot in the chest with a .22-caliber firearm and once in the head with a .25-caliber pistol. He had also received a skull fracture; his body lay in the hallway to the property beneath the body of his youngest son, Randall, who had been shot once in the head by a firearm of unknown caliber. Susan lay alongside her father and brother; she had received a single .25-caliber gunshot to the face in addition to a skull fracture.

Shirley Robison's body lay on her stomach in the living room; she had received a single .25-caliber gunshot wound to the head and a red-and-black plaid blanket had been placed over her body after death. Richard Jr. lay midway between the hallway and northwest bedroom of the property; he had received several gunshots to the head from a .25-caliber pistol. Gary was discovered lying parallel to the east wall of the northwest bedroom; he had been shot once in the back with a .22-caliber firearm and twice in the head with a .25-caliber firearm. A ballistics examination of the bullets determined the .25-caliber firearm used in the murders was an automatic Beretta pistol, whereas the .22-caliber bullets had been fired from a somewhat uncommon AR-7 ArmaLite semi-automatic rifle. Playing cards scattered upon a table indicated two or more family members had been playing a game of solitaire at the time of the shootings.

The time-lapse between the homicides and their discovery in addition to the perpetrator having turned the heating on within the property had resulted in the decedents' bodies being in an advanced state of decomposition, thus destroying potential physical evidence. Questioning of the sole family whose seasonal home had been close to the Robison cottage revealed they had not been present in their cabin on June 24 or 25; however, another couple informed investigators that sometime in the late afternoon of June 25, they had heard two men and a woman shouting, followed by the sound of gunfire—all emanating from the direction of Summerset. They had chosen not to investigate, believing the Robisons to be "shooting gulls on the beach."

Initial investigation Investigators rapidly determined the murders were premeditated and most likely committed by an individual or individuals known to one or more members of the family. Although an expensive ring belonging to Shirley was missing, no money or other items of value had been taken from the victims, thus discounting robbery as a motive. Furthermore, although Shirley Robison was nude from the waist down, no family member had been sexually assaulted, and her body had most likely been posed in this manner to deceive investigators into believing a sexual motive existed behind the murders.

All individuals whom the Robisons were known to have encountered in the nine days they had spent at Good Hart were eliminated from the inquiry, and theories pertaining to potential family links to organized crime circles were also discounted.

Prime suspect