Question: When did the state, that contains the county where Elmo is found, reinstate the death penalty?

Knowledge 1: Elmo, Montana
Elmo (Salish: sqʷe, "inlet in the lake") is a census-designated place (CDP) in Lake County, Montana, United States. The population was 143 at the 2000 census. [SEP] Knowledge 2: Lake County, Oregon
Lake County is in the high desert region known as the Oregon Outback, on the northwestern edge of the Great Basin. The county is generally divided between the communities around Lakeview and Paisley to the south and the communities around Christmas Valley, Fort Rock, and Silver Lake to the north. [SEP] Knowledge 3: Australia
Each state and major mainland territory has its own parliament — unicameral in the Northern Territory, the ACT and Queensland, and bicameral in the other states. The states are sovereign entities, although subject to certain powers of the Commonwealth as defined by the Constitution. The lower houses are known as the Legislative Assembly (the House of Assembly in South Australia and Tasmania); the upper houses are known as the Legislative Council. The head of the government in each state is the Premier and in each territory the Chief Minister. The Queen is represented in each state by a governor; and in the Northern Territory, the Administrator. In the Commonwealth, the Queen's representative is the Governor-General.The Commonwealth Parliament also directly administers the following external territories: Ashmore and Cartier Islands; Australian Antarctic Territory; Christmas Island; Cocos (Keeling) Islands; Coral Sea Islands; Heard Island and McDonald Islands; and Jervis Bay Territory, a naval base and sea port for the national capital in land that was formerly part of New South Wales. The external territory of Norfolk Island previously exercised considerable autonomy under the Norfolk Island Act 1979 through its own legislative assembly and an Administrator to represent the Queen. In 2015, the Commonwealth Parliament abolished self-government, integrating Norfolk Island into the Australian tax and welfare systems and replacing its legislative assembly with a council. Macquarie Island is administered by Tasmania, and Lord Howe Island by New South Wales.
Knowledge 1: Elmo, Montana
Elmo (Salish: sqʷe, "inlet in the lake") is a census-designated place (CDP) in Lake County, Montana, United States. The population was 143 at the 2000 census. [SEP] Knowledge 2: Lake County, Oregon
Lake County is in the high desert region known as the Oregon Outback, on the northwestern edge of the Great Basin. The county is generally divided between the communities around Lakeview and Paisley to the south and the communities around Christmas Valley, Fort Rock, and Silver Lake to the north. [SEP] Knowledge 3: Capital punishment in the United States
Other states with long histories of no death penalty include Wisconsin (the only state with only one execution), Rhode Island (although later reintroduced, it was unused and abolished again), Maine, North Dakota, Minnesota, West Virginia, Iowa, and Vermont. The District of Columbia has also abolished the death penalty; it was last used in 1957. Oregon abolished the death penalty through an overwhelming majority in a 1964 public referendum but reinstated it in a 1984 joint death penalty/life imprisonment referendum by an even higher margin after a similar 1978 referendum succeeded but was not implemented due to judicial rulings.
Knowledge 1: Elmo, Montana
Elmo (Salish: sqʷe, "inlet in the lake") is a census-designated place (CDP) in Lake County, Montana, United States. The population was 143 at the 2000 census. [SEP] Knowledge 2: Lake County, Oregon
Lake County is in the high desert region known as the Oregon Outback, on the northwestern edge of the Great Basin. The county is generally divided between the communities around Lakeview and Paisley to the south and the communities around Christmas Valley, Fort Rock, and Silver Lake to the north. [SEP] Knowledge 3: List of territorial entities where English is an official language
The following is a list of territories where English is an official language, that is, a language used in citizen interactions with government officials. In 2015, there were 54 sovereign states and 27 non-sovereign entities where English was an official language. Many country subdivisions have declared English an official language at the local or regional level.

Answer: 1984