Knowing the law and local town ordinances can be complicated but if you want to effect change, it's helpful to understand them as best as you can. You can call your local animal shelter or police department and ask them what the law is in your area. And while the Humane Society of the United States is not a law enforcement agency, they can offer advise at 202.452.1100 or 866.720.2676 M-F 8am to 11pm.
OUTSIDE Dog laws differ if the dog is tethered (on a leash or chain) or penned (free in a fenced in area). Tethered dogs cannot be chained outside during an official weather advisory period.
A law has been passed that makes it illegal for dogs to be kept outdoors for longer than half an hour during extremely hot or cold temperatures. Owners can’t leave their pets tied up if it’s colder than +0 degrees Celsius or warmer then +32 degrees. (This law was named to honor a puppy named Libre who was rescued from a terrible living situation. Though only seven weeks old, Libre endured more neglect and abuse than any animal should. It was doubtful if little Libre would survive. Thanks to the brave actions of a good Samaritan who tipped off animal rescuers, he was saved and has recovered from his horrible ordeal.)
How about the dog who is outside 24/7 but not tethered? The dog must have sufficient shelter, water and food.
The law (in abbreviated form) reads this way: “The Owner or Custodian of a dog left outdoors in inclement weather must provide the dog with shelter appropriate to its breed, physical condition, and the climate. INCLEMENT WEATHER: weather conditions likely to adversely affect the health or safety of the dog (includes rain, sleet, ice, snow, wind, extreme heat or cold, and anything else that is likely to adversely affect the well-being of the dog). DOG LEFT OUTDOORS: A dog that is outside in inclement weather without ready access to, or the ability to enter a house, apartment building, office building, or any other permanent structure that meets the minimum standards for shelter required by this law. PHYSICAL CONDITION: includes any special medical needs of a dog due to disease, illness, injury, age, or breed which an owner or custodian should reasonably know about.” https://yourspca.org/newsevents/law-calls-for-proper-outdoor-animal-sheltering-in-inclement-weather/
Since the laws may not align with what most consider inhumane, Animal Control Officers do not have the authority to punish owners. If you are fortunate enough to have an ACO in your area who does not believe that dogs should live outside 24/7 (regardless of the conditions) he/she can help bridge the gap between what is legal and what is inhumane by offering education and insight.
Table of State Dog Tether Laws - https://www.animallaw.info/topic/table-state-dog-tether-laws
Document regarding dogs left in vehicles: https://www.cga.ct.gov/2015/rpt/pdf/2015-R-0192.pdf