SPOKANE, Wash. — Grant County Sheriff Tom Jones joins a handful of other Washington sheriffs who say they will not enforce Initiative 1639, which places stiff requirements on the sale and ownership of semi-automatic rifles. 

“I agree with my other county sheriff colleagues. I am instructing my deputies not to enforce Initiative 1639 in Grant County while the constitutional validity remains in argument at the federal courts level. I swore an oath to defend our citizens and their constitutionally protected rights. I do not believe the popular vote overrules that,” Jones said in a statement.

“If the courts later rule the validity of this new law, at that time I will partner closely with our prosecutor’s office to ensure the best plan moving forward. Grant County has a very large voter base of citizens that are pro Second Amendment. They, we, have a right to have this challenge and appeals process play out before moving forward," he continued. 

Initiative 1639 – approved in November – raises the age to purchase a semi-automatic rifle from 18 to 21, calls for enhanced background checks and requires buyers to complete a firearm safety course. The initiative also holds gun owners accountable if someone uses their firearm to harm themselves or others.

The National Rifle Association and the Second Amendment Foundation have also filed a joint lawsuit challenging the initiative.

Spokane County Sheriff Ozzie Knezovich called I-1639 unconstitutional in a Facebook post last Thursday. 

In a thread on the SCSO Facebook page, Knezovich was asked his stance on I-1639 and if he planned on enforcing the law or not. Knezovich said that other sheriffs are "grandstanding" by not supporting it.

"These other sheriffs are purely grandstanding when they say they won't enforce 1639 because there is nothing for us to enforce," he wrote in a response.

RELATED: Spokane County Sheriff calls I-1639 'unconstitutional on the state and federal level'

RELATED: 'There is no such thing as an assault weapon': Spokane Sheriff Knezovich discusses I-1639

Okanogan County Sheriff Anthony Hawley announced in a news release Monday that the "initiative, as currently written, appears to be unenforceable due to the unclear language and lacking appropriate definitions." He also said deputies in his office would continue to investigate such cases and report their findings. 

Chelan County Sheriff Brian Burnett also said on Facebook that he is in agreement with a Jan. 1 statement from the Washington State Sheriffs Association expressing opposition to I-1639. He also posted a letter he wrote to The Wenatchee World voicing his opposition to the initiative during election season.

"As your Chelan County sheriff, I am committed to serving the citizens in a way that both protects their Constitutional right while being both fair and impartial while upholding the rule of law," Burnett wrote. 

Stevens County Sheriff Brad Manke recently announced he too would not enforce I-1639. 

A Facebook post from Manke reads: 

"As you are well aware Initiative 1639 was voted into law by the voters in the State of Washington in the last election. This law is highly debated and is being contested on multiple fronts.

It will be the position of the Stevens County Sheriff's Office that we will not take enforcement action (make custodial arrests or issue citations) on alleged violations of this law unless imminent danger exists to the public. I join the 73% of Stevens County voters who voted against this initiative."

Douglas County Sheriff Kevin Morris also released the following statement on Friday. 

The statement reads in part: 

"In response to the numerous requests for comment by the media and citizens of Douglas County see the following;  I understand the multitude of concerns, questions, and uncertainties raised by the recently passed initiative, I-1639, which alters the existing gun laws throughout Washington State.  As the Sheriff of Douglas County, my highest priority is protecting our community and safeguarding the rights of all residents I was elected to represent.  The Douglas County Sheriff’s Office has a proud tradition of common sense policing, a perspective we will continue to apply in our operations as it relates to I-1639. 

As Sheriff, I believe strongly in the rules, laws, and constitutions of our State and Nation.  These rights form the bedrock of our great Country.  Initiative 1639 is currently being challenged through the formal legal process.  While the Courts work to determine the legality of the law, the Douglas County Sheriff’s Office will continue their work as they always have.  We believe in creating enforcement priorities to ensure that we address the most serious problems affecting our residents.  We are committed to addressing the opioid epidemic, mental health concerns, and violent crimes, all of which are serious concerns for our strong community."

Benton County Sheriff Jerry Hatcher also wrote in a letter that I-1639 as written is “non-enforceable,” while Adams County Sheriff Dale Wagner wrote that it “appears to violate the 2nd Amendment.”

Benton County is located in south-central Washington and includes the cities of Richland and Kennewick.

All sheriffs announcing they will not enforce the initiative join the Lewis County Sheriff's Office and Republic Police Chief Loren Culp, who announced shortly after the November election that they wouldn't enforce the new law.

Klickitat County Sheriff Bob Songer also announced he would not enforce I-1639. He told the Yakima Herald-Republic that he believes the new law is unconstitutional.

In November, Culp proposed that his jurisdiction become a “2nd Amendment Sanctuary City” on the police department’s Facebook page.

Culp said the proposed legislation would “prevent federal and state infringement on the right to keep and bear arms; nullifying all federal and state acts in violation of the 2nd Amendment to the Constitution of the United States and Article 1 Section 24 of the Washington State Constitution.”

The term “sanctuary city” often describes a local government that does not use its own resources, such as local police departments, to enforce federal immigration laws.

RELATED: Republic City Council delays vote on 2nd Amendment sanctuary city ordinance

Spokane City Council member Breean Beggs, who is a lawyer and previously served as executive director of the Center for Justice civil rights firm, said it's an accepted legal principal that law enforcement use their own judgment to enforce laws.

RELATED: Could Washington town face consequences for not enforcing I-1639?

The Associated Press contributed to this report.