Crime Solvers Central
Crime Solvers Central
298 Cases Solved. Advancing justice for missing persons, unsolved homicides, unidentified and unclaimed remains.
William Sinclair missing person case profile photo

William Sinclair Missing Person Case

Last seen in Hopkins, Minnesota on Apr 28, 1978

Victim Details

Jun 28, 2013

Jan 9, 2024

William

Sinclair

77

29

68 inches

130 lbs

White / Caucasian

Male

Apr 28, 1978

Hopkins

Minnesota

Hennepin County

No

31342

Hopkins Police Department

Hopkins

Minnesota

Hennepin County

55343

1010 1st Street South, Minnesota

9522585321

Local

Law Enforcement

https://www.hopkinsmn.com/308/Police

78004005

Hopkins Police Department

Brown

Hazel

Hazel

Oct 7, 2026


Area Last Seen:

Case Description

Any updates on this case? Let us know!
Summary based on the NamUs case record (MP20829) and 10 other sources
William D. Sinclair, a 29-year-old man from Hopkins, Minnesota, disappeared on April 28, 1978, under suspicious circumstances. He was last seen attending a party on 11th Avenue South, near the Hopkins Police Department. After the party, Sinclair vanished, and his car was found abandoned nearby. The keys were still in the ignition, and his eyeglasses were discovered on the floor of the vehicle, but there were no signs of him at the scene.

Sinclair was last seen wearing a blue jacket, a dark blue sweater, a light brown shirt, and blue jeans. He also had a three- to four-inch surgical scar on his abdomen, which could aid in identification. Despite extensive searches, there have been few leads over the years, and his case remains unsolved. Authorities continue to list his disappearance as endangered, with no clear evidence indicating whether foul play was involved.

Sinclair's family and law enforcement have been seeking answers for decades, but his fate remains a mystery.
Last Seen: Apr 28, 1978

Links to Additional Sources (10)

See any mistakes? Let us know!
  • Missing Person / NamUs
  • Hopkins boy
  • William D. Sinclair - The Charley Project
  • Hopkins police: Missing boy found dead press conference [RAW]
  • U.S. Missing Persons - Doe Network
  • Top 10 Most Challenged Books and ... - American Library Association
  • MN - William Sinclair, 29, Hopkins, 28 April 1978 | Websleuths
  • Ann - William D Sinclair Age 29 Missing 4-28-1978 ... - Facebook
  • William Sinclair - a picaresque life reviewed - Pissed-off Toff
  • William Sinclair (1640-1686) - Mémorial Find a Grave

    • Possible Unidentified Matches (8)

    Unidentified remains cases whose details are consistent with this person, ranked by how closely they compare. Fields that are unknown in either case are left out of the score.

    81%Moderate
    John Doe — Minneapolis, Minnesota - unidentified case UP763
    John Doe — Minneapolis, Minnesota
    UP763 • Found Dec 16, 2003
    View case
    Sex ✓Male
    Age 100%Est. 30–45 vs 29 when missing
    Race 100%White
    Location 100%8 mi away, same county
    TimingFound 26 years after last seen
    Height 100%5'8" vs 5'8"
    Weight 100%131 lb vs 130 lb
    Hair 100%Brown vs Brown
    Eyes 30%Blue vs Hazel
    80%Moderate
    John Doe — Minneapolis, Minnesota
    UP124186 • Found Sep 25, 1995
    View case
    Sex ✓Male
    Age 100%Est. 30–45 vs 29 when missing
    Race 100%White
    Location 100%8 mi away, same county
    TimingFound 17 years after last seen
    Height 84%5'10" vs 5'8"
    Weight 80%156 lb vs 130 lb
    Hair 100%Brown vs Brown
    79%Possible
    John Doe — Burnsville, Minnesota - unidentified case UP4743
    John Doe — Burnsville, Minnesota
    UP4743 • Found Aug 24, 2005
    View case
    Sex ✓Male
    Age 100%Est. 20–30 vs 29 when missing
    Race 100%White
    Location 99%12 mi away, same state
    TimingFound 27 years after last seen
    Height 84%5'6" vs 5'8"
    Weight 100%123 lb vs 130 lb
    Hair 60%Black vs Brown
    Eyes 60%Brown vs Hazel
    78%Possible
    John Doe — St Paul, Minnesota
    UP148173 • Found May 23, 2025
    View case
    Sex ✓Male
    Age 100%Est. 28–42 vs 29 when missing
    Race 100%White
    Location 98%16 mi away, same state
    TimingFound 47 years after last seen
    Height 100%5'7" vs 5'8"
    Weight 83%154 lb vs 130 lb
    76%Possible
    John Doe — Prior Lake, Minnesota
    UP4815 • Found Sep 27, 2003
    View case
    Sex ✓Male
    Age 100%Est. 20–30 vs 29 when missing
    Race 100%White
    Location 99%15 mi away, same state
    TimingFound 25 years after last seen
    Height 84%5'6" vs 5'8"
    Hair 60%Black vs Brown
    76%Possible
    John Doe — Minneapolis, Minnesota - unidentified case UP154368
    John Doe — Minneapolis, Minnesota
    UP154368 • Found May 8, 1997
    View case
    Sex ✓Male
    Age 100%Est. 40–50 vs 29 when missing
    Race 60%Hispanic
    Location 100%7 mi away, same county
    TimingFound 19 years after last seen
    Height 100%5'9" vs 5'8"
    Weight 100%128 lb vs 130 lb
    Hair 60%Black vs Brown
    Eyes 60%Brown vs Hazel
    75%Possible
    John Doe — Minneapolis, Minnesota
    UP765 • Found Oct 5, 1996
    View case
    Sex ✓Male
    Age 100%Est. 35–45 vs 29 when missing
    Race 100%White
    Location 100%8 mi away, same county
    TimingFound 18 years after last seen
    Height 68%5'5" vs 5'8"
    75%Possible
    John Doe — St. Paul, Minnesota
    UP4806 • Found Jun 4, 1978
    View case
    Sex ✓Male
    Age 100%Est. 25–30 vs 29
    Race 100%White
    Location 99%15 mi away, same state
    TimingFound 5 weeks after last seen
    Height 20%6'2" vs 5'8"
    Weight 11%190 lb vs 130 lb
    Hair 100%Brown vs Brown

    These comparisons are generated automatically from public NamUs case data and are not confirmed identifications. Only DNA, dental or fingerprint comparison by investigators can confirm an identity. If you believe two cases are connected, contact the agency handling the unidentified case.

    Unidentified photos are blurred because many are post-mortem. Tap a photo to reveal it.

    Latest News

    View All

    Forum Posts (3)

    I've been diving into the mysterious disappearance of William D. Sinclair for a while now, and... ...Read More
    05/06/2024
    Has anyone else looked into the area around where William Sinclair’s car was found? I’ve been diving... ...Read More
    08/03/2023
    I was re-reading about the William D. Sinclair case, and something that stands out to me are the... ...Read More
    07/01/2023

    Other Missing Cases from Hopkins, Minnesota

    Abdikadir Abdi missing person case in Hopkins, Minnesota

    Abdikadir Abdi

    Missing: Nov 3, 2008
    Abdikadir Ali Abdi, a 17-year-old from Hopkins, Minnesota, went missing on November 3, 2008. His ...Read More
    Charles Erickson missing person case in Hopkins, Minnesota

    Charles Erickson

    Missing: Feb 17, 2000
    Charles Arthur Erickson, a 40-year-old man from Hopkins, Minnesota, disappeared on February 17 ...Read More