An above-ground pipeline running through a wooded area; cloudy skies.

Pipeline Projects

State attor­neys gen­er­al are address­ing ener­gy infra­struc­ture projects and needs in their states and regions, includ­ing advo­cat­ing for the inter­ests of com­mu­ni­ties that would be affect­ed by pro­posed pipeline projects.

Advo­ca­cy in the States

The Dako­tas

The Dako­ta Access Pipeline is intend­ed to car­ry crude oil from North Dako­ta to Illi­nois, includ­ing pass­ing under Lake Oahe, which strad­dles North Dako­ta and South Dako­ta. The Stand­ing Rock and the Cheyenne Riv­er Sioux Tribes rely on Lake Oahe for water, agri­cul­ture, indus­try and reli­gious and med­i­c­i­nal prac­tices. Despite this, the U.S. Army Corps of Engi­neers grant­ed an ease­ment to con­struct the pipeline with­out prepar­ing an Envi­ron­men­tal Impact State (EIS) as required by the Nation­al Envi­ron­men­tal Pol­i­cy Act (NEPA).


  • July 2016

    In July 2016, the Tribes filed a law­suit against the Army Corps chal­leng­ing the issuance of the ease­ment as vio­lat­ing NEPA.

  • July 2020

    In July 2020, the fed­er­al dis­trict court in the Dis­trict of Colum­bia issued an order sid­ing with the tribes in find­ing that the Army Corps had vio­lat­ed NEPA and requir­ing that the pipeline be shut down in 30 days.

  • July 2020

    The Army Corps, in July 2020, appealed the dis­trict court deci­sion to the Court of Appeals for the Dis­trict of Colum­bia Circuit.

  • Sep­tem­ber 2020

    In Sep­tem­ber 2020, Mass­a­chu­setts Attor­ney Gen­er­al Mau­ra Healey led a coali­tion of 18 attor­neys gen­er­al in fil­ing an ami­cus brief in sup­port of the Tribes. The brief not­ed that the dis­trict court rul­ing was appro­pri­ate and should be affirmed as courts have repeat­ed­ly con­firmed that fed­er­al agen­cies are to take action to com­ply with NEPA before the agency acts. Fur­ther, the attor­neys gen­er­al point­ed out that the project’s oppo­nents are seek­ing to sub­vert NEPA by attempt­ing to inject eco­nom­ic con­sid­er­a­tions into the NEPA review process when it is clear that pro­tect­ing against eco­nom­ic harm is not one of the statute’s objectives.


Enbridge Inc.’s Line 5 pipeline car­ries oil and nat­ur­al gas liq­uids from Supe­ri­or, Wis­con­sin to Sar­nia, Ontario. After the com­pa­ny dis­cov­ered an anchor sup­port had shift­ed deep below the sur­face in the pipeline’s cross­ing between Lakes Michi­gan and Huron in the Straits of Mack­inac, Michi­gan Attor­ney Gen­er­al Dana Nes­sel filed a tem­po­rary restrain­ing order and pre­lim­i­nary injunc­tion in Michi­gan state court. Attor­ney Gen­er­al Nes­sel empha­sized that Enbridge failed to pro­vide the state with need­ed infor­ma­tion on the pipeline’s safe­ty. The court grant­ed the restrain­ing order and injunc­tion and ordered Enbridge to tem­porar­i­ly halt oper­a­tions across the Line 5 pipeline. 

Mon­tana and Nebraska

The Key­stone XL Pipeline was a pro­posed expan­sion to an exist­ing pipeline sys­tem to trans­port crude oil from Alber­ta, Cana­da and the Bakken shale for­ma­tion in Mon­tana to exist­ing pipeline facil­i­ties near Steele City, Nebras­ka. The pipeline would have crossed near­ly one thou­sand bod­ies of water, caus­ing sig­nif­i­cant impacts to water qual­i­ty, habi­tat, and endan­gered species.


  • July 2019

    In July 2019, envi­ron­men­tal groups filed a law­suit chal­leng­ing the Key­stone XL Pipeline, argu­ing that reis­suance of Nation­wide Per­mit 12 (NWP 12) and its appli­ca­tion to Key­stone XL by the Army Corps vio­lat­ed the Nation­al Envi­ron­men­tal Pol­i­cy Act (NEPA), the Clean Water Act, and the Endan­gered Species Act (ESA).

  • May 2020

    In May 2020, a fed­er­al dis­trict court in Mon­tana vacat­ed NWP 12 due to the Army Corps’ fail­ure to con­duct the required ESA con­sul­ta­tion, effec­tive­ly block­ing con­struc­tion of Key­stone XL. The court lat­er lim­it­ed its order to vacate NWP 12 for only new pipeline projects, and the Supreme Court fur­ther lim­it­ed the impact to only the Key­stone XL pipeline. Lat­er in May, the Army Corps, the pipeline devel­op­er, and the state of Mon­tana appealed the dis­trict court’s deci­sion to the U.S. Court of Appeals for the Ninth Circuit.

  • Decem­ber 2020

    In Decem­ber 2020, a coali­tion of 12 state attor­neys gen­er­al led by Cal­i­for­nia Attor­ney Gen­er­al Xavier Becer­ra filed an ami­cus brief in the Ninth Cir­cuit in sup­port of the envi­ron­men­tal groups’ oppo­si­tion to the efforts to rein­state NWP 12. In their brief, the attor­neys gen­er­al assert­ed that NWP 12 is invalid because the Army Corps failed to con­sult with fed­er­al wildlife agen­cies regard­ing the impacts that the per­mit might have on fed­er­al­ly list­ed endan­gered and threat­ened species, as required by the ESA.

  • Post­script

    Post­script: After the Biden admin­is­tra­tion can­celed the Key­stone leas­es by exec­u­tive order, in June 2021, Key­stone announced that it would ter­mi­nate the project.