Separation of Powers means that the institutions are separate, not the powers
The branches are independent and equal, and no one can be in more than one branch, with the exception of the Vice President being the tie-breaker in the Senate if necessary
The President can veto a bill but Congress can override the veto with a two thirds vote in each chamber of Congress
Obama vetoed the Keystone XL Pipeline
Trump vetoed the resolution that revoked his declaration of national emergency on the Mexican Border
Congress revoked Trump's veto on the National Defence Authorization Act
The President can nominate a Supreme Court judge to the Senate and also hold the power of pardon
Obama appointed Sonia Sotomayor and Elena Kagan
Trump appointed Neil Gorsuch, Brett Kavanaugh, and Amy Coney Barett
Henry Ford pardoned Nixon
Congress can amend, reject, and delay the president's proposals
Biden's pick of Neera Tanden as Director of Office of Management and Budget
Obama wanted increased gun control after the Sandy Hook shooting but nothing passed
Congress holds Power of the Purse and can deny a president funding
Trump's border wall - money wasn't given by Congress
Vietnam War didn't end, Congress just stopped funding it
The Senate can refuse to approve the President's appointments
Obama's appointment of Robert Wilking to the DC Court of Appeals was not approved
The Senate can refuse to ratify the president's treaties
Convention on the Rights of Persons with Disabilities passed 61-38 but needed 5 more votes to be ratified
Congress can impeach the President and have powers to remove them from office
Trump's impeachment over increased US Airforce spending on refuelling at a Scottish airport near a Trump owned resort - conflict of interest
The House had started the impeachment process against Nixon but he was pardoned by Gerald Ford
Congress can propose constitutional amendments to overturn judicial decision
National income tax was declared unconstitutional and reversed by the ratification of the 13th amendment in 1913
There have been attempts to pass amendments banning flag desecration and prayer in state schools but both have been unsuccessful
The Senate can refuse to approve nominations to the federal courts and impeach members of federal courts
Obama's nomination of Merrick Garland to the Supreme court expired, allowing Trump to appoint Neil Gorsuch
Thomas Porteous, Louisiana Federal judge, was successfully impeached and removed due to bribery and perjury
The Federal Courts can deem a law to be unconstitutional
Defense of Marriage Act was deemed unconstitutional and was a major advance for legalising same-sex marriage
The Supeme Court can deem a President's actions to be unconstitutional
George Bush - Special military commissions to try suspected members of Al-Qaeda in the Hamdan v Rumsfeld case 2006
Trump v Mazar and Trump v Vance - the president is not above the law, even when in office