Since President Donald Trump took office in January, Colorado Attorney General Phil Weiser has sued to block the president’s policies 63 times, according to his office.
And he’s mostly won.
A review of Weiser’s cases shows courts have partially or fully blocked Trump administration policies from taking effect, at least temporarily, in 34 cases, left the policies in place for now in eight cases, and are still considering 21 cases.
Weiser, a Democrat running for governor in 2026, joined other state attorneys general or governors on all of the cases. The decisions face appeals and are largely preliminary.
The 63 cases Weiser has brought so far eclipse the 11 he filed against Trump during the Republican’s first presidency.
Here is where the lawsuits stand as of March 23, 2026.
● 34 Weiser cases blocking Trump policy (for now)
Immigration
Weiser sued to block Trump’s attempt to end birthright citizenship, which guarantees that people born in the U.S. are citizens, regardless of whether their parents are in the country legally.
- Read more: Colorado, 21 other states sue Trump to block order ending birthright citizenship
- Case here: State of New Jersey vs. Trump, Court of Appeals for the First Circuit
Weiser sued to block Trump’s transfer of Medicaid data to immigration agencies.
- Read more: Colorado, 19 other states sue to stop transfer of Medicaid data to immigration agencies
- Case here: State of California vs. U.S. Department of Health and Human Services, District Court, N.D. California
Weiser sued to block Trump’s policy requiring state agencies to verify individuals’ immigration status before allowing them to access federal aid.
Climate and environment
Weiser sued to block Trump’s attempt to pause federal funding for electrical vehicle charging projects.
Weiser sued to block Trump’s attempt to stop the development of wind energy.
Data privacy
Weiser sued to block Elon Musk and the Department of Government Efficiency, known as DOGE, from accessing private taxpayer data.
- Read more: All the lawsuits Colorado has filed against the Trump administration so far
- Case here: State of New York vs. Donald J. Trump, District Court, S.D. New York
Weiser sued to block Trump’s demand that states turn over personal information about people enrolled in the Supplemental Nutrition Assistance Program, known as SNAP.
- Read more: Colorado jumps onto lawsuit against USDA over demand for personal information of SNAP recipients
- Case here: State of California vs. United States Department of Agriculture, District Court, N.D. California
Elections
Weiser sued to block Trump’s attempt to withhold funding to states that do not require proof of citizenship to register to vote and vote and require all ballots be counted on Election Day (many states allow ballots that arrive by mail after Election Day to be counted as long as they were postmarked by Election Day).
Weiser sued to block Trump’s announced move of U.S. Space Command from Colorado Springs to punish Colorado for its vote by mail system. Weiser added Trump funding cuts to SNAP, transportation grants, denial of FEMA relief funds and other issues to this lawsuit.
- Read more: Colorado attorney general sues Trump administration over Space Command HQ relocation to Alabama
- Read more: Federal judge blocks Trump threats to remove Coloradans from SNAP
- Case here: State of Colorado, The v. Trump, District Court, D. Colorado
Federal employee firings
Weiser sued to block Trump’s attempt to close several federal agencies, including the Institute of Museum and Library Services.
Weiser sued to block Trump’s attempt to cut staff at the U.S. Department of Health and Human Services.
Funding cuts
Weiser sued to block Trump’s attempts to:
- Freeze federal funding.
- Cut National Institute of Health pay for research universities and medical schools.
- End COVID-related grants.
- Reduce AmeriCorps workforce.
- Withhold transportation funding from states that did not help the feds enforce immigration law.
- Cut Department of Defense research grants to universities.
- Withhold U.S. Department of Education funding for after school, summer and other education programs.
- End a FEMA grant program to strengthen infrastructure before disasters.
- Place immigration enforcement conditions on Homeland Security funds.
- Cut federal funding for state energy programs.
- Place immigration enforcement conditions on U.S. Department of Justice grants for crime victims and survivors.
- Suspend during the government shutdown the Supplemental Nutrition Assistance Program.
- Cut teen sexual health education programs from states unless they remove language about gender identity.
- Cut U.S. Department of Education funding for mental health services.
- Restrict federal funding for survivors of domestic violence and other violent crimes who are undocumented immigrants.
- Cut off Supplemental Nutrition Assistance Program benefits for lawful permanent residents.
- Interfere with federal grants for emergency management, disaster-relief, and homeland security operations.
- Cut funding for Colorado’s poorest families through the Temporary Assistance for Needy Families, Social Services Block Grant and Child Care and Development Fund programs.
- Cut more than $600 million in public health funding from some Democratic states, including Colorado.
- Withhold education funding from agencies that did not end DEI initiatives.
Transgender rights
Weiser sued to block Trump’s attempt to ban transgender youth medical care and treatment.
- Read more: Two Colorado hospitals to resume gender-affirming care for youth
- Case here: State of Washington, et al. vs. Trump, Court of Appeals for the Ninth Circuit
Housing
Weiser sued to block the U.S. Department of Housing and Urban Development from reducing funding available for housing for people experiencing homelessness.
Tariffs
Weiser sued to block Trump’s attempt to impose tariffs without approval from Congress.
- Read more: As US Supreme Court rules against Trump’s tariffs, Colorado companies look at implications
- Case here: V.O.S. Selections, Inc. vs. Trump, Court of Appeals for the Federal Circuit
● 8 Weiser cases not blocking Trump policy (for now)
Federal employee firings
Weiser sued to block Trump’s mass firing of federal employees.
Weiser sued to block Trump’s mass firing of U.S. Department of Education employees.
Funding cuts
Weiser sued to block Trump’s attempt to eliminate K-12 teacher training grants.
- Read more: Colorado, seven other states sue Trump administration after abrupt end to teacher training grants
- Case here: State of California vs. U.S Department of Education, District Court, D. Massachusetts
Weiser sued to block Trump’s cuts to programs and grants from the National Science Foundation.
Weiser sued to block Trump’s delay of medical research grants.
Weiser sued to block Trump’s cancellation of a $7 billion solar program.
Healthcare
Weiser sued to block Trump’s changes to Affordable Care Act enrollment.
- Case here: State of California vs. Centers for Medicare & Medicaid Services, District Court, D. Massachusetts
Weiser sued to overturn Trump’s blocking of Medicaid payments to Planned Parenthood clinics.
● 21 Weiser cases pending rulings
Climate and environment
Weiser sued to restore funding for two grant programs established by the Bipartisan Infrastructure Law in 2021 aimed at bolstering electric vehicle charging networks.
- Case here: State of California v. United States Department of Transportation, District Court, W.D. Washington
Weiser sued to overturn Trump’s plan to ban California’s rule banning the sale of new gas-powered cars by 2035.
Weiser sued to block President Trump’s “energy emergency” executive order aimed at fast-tracking fossil fuel projects.
Weiser sued to challenge the Trump administration’s disapproval of Colorado’s regional haze plan to reduce air pollution and improve air quality.
Weiser is challenging the U.S. Environmental Protection Agency attempt to rescind its 2009 endangerment finding – the agency’s determination that greenhouse gas pollution from motor vehicles drives climate change and endangers public health and welfare.
Weiser sued to block an emergency order issued by the U.S. Department of Energy requiring the coal-fired Craig Unit 1 power plant in Moffat County to be available until March 30.
- Read more: Colorado sues to block Energy Department orders keeping Craig coal unit open
- Case here: State of Colorado v. DOE, Court of Appeals for the D.C. Circuit
Funding cuts
Weiser sued to block Trump’s cuts to federal agencies using an obscure federal regulation.
- Case here: State of New Jersey v. U.S. Office of Management and Budget, District Court, D. Massachusetts
Weiser sued the Trump administration for damages, interest and fees related to its cancelation of solar grants.
Weiser sued to block the Trump administration’s efforts to dismantle the Consumer Financial Protection Bureau.
Weiser sued to block Trump’s attempts to terminate funding for energy and infrastructure programs created by Congress.
- Read more: Colorado AG sues to claw back $600 million in energy research grants canceled by Trump
- Case here: State of California v. Wright, District Court, N.D. California
Weiser sued to block Trump’s attempts to end millions in grants to states to prevent targeted violence and terrorist attacks.
Weiser sued to block threats from the U.S. Department of Housing and Urban Development to withhold funding from state and local fair housing enforcement agencies.
Weiser sued to block requirements from the U.S. Department of Agriculture that states put immigration and other conditions on programs and grants.
- Case here: Commonwealth of Massachusetts v. U.S. Department of Agriculture, District Court, D. Massachusetts
Gun regulations
Weiser sued to block Trump’s plan to allow the sale of forced-reset triggers that make semiautomatic rifles fire more rapidly.
Education
Weiser sued to block a Trump policy that restricts eligibility for a federal program allowing student loan relief for government and nonprofit employees.
- Case here: Commonwealth of Massachusetts v. U.S. Department of Education, District Court, D. Massachusetts
Weiser sued to block a Trump policy requiring universities to report new data about how race is used in admissions to the U.S. Department of Education.
Immigration
Weiser sued to block a Trump policy imposing a $100,000 fee on new H-1B visa petitions.
Transgender rights
Weiser sued to challenge a Trump administration policy seeking to ban health care providers who provide gender-affirming care from Medicare and Medicaid programs.
Weiser sued to challenge the Trump administration’s effort to condition federal health, education, and research funding on states’ compliance with a presidential executive order that seeks to deny the existence of transgender people.
- Case here: State of New York v. U.S. Department of Health and Human Services, District Court, D. Rhode Island
Healthcare
Weiser sued to challenge the Trump administration’s overhaul of the childhood vaccine schedule.
- Read more: Colorado pushes back against CDC’s new childhood vaccine recommendations
- Case here: State of Arizona v. Kennedy, District Court, N.D. California
Tariffs
Weiser sued to challenge Trump’s efforts to impose tariffs relying on Section 122 of the Trade Act of 1974.
This story will be updated as Weiser brings more cases and as court decisions occur.