T he constitutional system of checks and balances and the separation of powers among the legislative, executive, and judicial branches is a cornerstone of the American system of government. By separating and checking powers in this way, the Framers hoped to prevent any person or group from seizing control over the nation's government. For example, the Framers checked congressional legislative power by providing the President the power to veto legislation and, in turn, checked the President's veto power by providing Congress a means to override that veto. Over time, it has become clear that the presidential veto power, even when not formally exercised, provides the President with an important tool to engage in the legislative process. Most Presidents have exercised their veto power in an effort to block legislation. Of 45 Presidents, 37 have exercised their veto power. As of the end of 2019, Presidents have issued 2,580 vetoes, and Congress has overridden 111. President George W. Bush vetoed 12 bills during his presidency. Congress attempted to override six of them and succeeded four times. President Barack Obama also vetoed 12 bills during his presidency. Congress attempted to override six of them and succeeded once. Presidents have also attempted to influence the shape of legislation through the use of veto threats. Since the 1980s, formal, written Statements of Administration Policy (SAPs, pronounced "saps") have frequently been used to express the President's support for or opposition to particular pieces of legislation. SAPs sometimes threaten to use the veto power if the legislation reviewed reaches the President's desk in its current form. Among the George W. Bush Administration (2001-2009) and the Obama Administration (2009-2017) SAPs examined later in this report, for example, 24% and 48%, respectively, contained a veto threat. This report begins with a brief discussion of the veto power and Congress's role in the veto process. It then examines the ways Presidents communicate their intention to veto, oppose, or support a bill. The report then provides and discusses summary data on veto threats and vetoes during the Bush and Obama Administrations. As specified by the U.S. Constitution (Article I, Section 7), the President has 10 days, Sundays excepted, to act once he has been presented with legislation that has passed both houses of Congress and either reject or accept the bill into law. Within those 10 days, Administration officials consider various points of view from affected agencies (as is the case throughout the legislative process) and recommend a course of action to the President regarding whether or not to veto the presented bill. The President has three general courses of action during the 10-day presentment period: The President may sign the legislation into law, take no action and allow the bill to become law without signature after the 10 days, or reject the legislation by exercising the office's veto authority. The President may reject legislation in two ways. The President may veto the bill and "return it, with his Objections to that House in which it shall have originated." This action is called a "regular" or "return" veto (hereinafter return veto). Congress typically receives the objections to the bill in a written veto message. If Congress has adjourned during the 10-day period, the President might also reject the legislation through a "pocket veto." This occurs when the President retains, but does not sign, presented legislation during the 10-day period, with the understanding that the President cannot return the bill to a Congress that has adjourned. Under these circumstances, the bill will not become law. A pocket veto is typically marked by a type of written veto message known as a "Memorandum of Disapproval." As discussed in greater detail below, this practice has sometimes been controversial, because arguably it prevents Congress from attempting to override the President's veto. A President's return veto may be overridden, or invalidated, by a process provided for in Article 1, Section 7, of the U.S. Constitution. To override a return veto, Congress may choose to "proceed to reconsider" the bill. Passage by two-thirds of Members in each chamber is required to override a veto before the end of the Congress in which the veto is received. Neither chamber is under any constitutional, legal, or procedural obligation to conduct an override vote. It is not unusual for either chamber of Congress to make no effort to override the veto if congressional leaders do not believe they have sufficient votes to do so. If a two-thirds vote is successful in both chambers, the President's return veto is overridden, and the bill becomes law. If a two-thirds vote is unsuccessful in one or both chambers, the veto is sustained, and the bill does not become law. In contrast, Congress cannot override the President's pocket veto. By definition, a pocket veto may occur only when a congressional adjournment prevents the return of the vetoed bill. If a bill is pocket vetoed while Congress is adjourned, the only way for Congress to pass a version of the policy contained in the vetoed bill is to reintroduce the legislation as a new bill, pass it through both chambers, and present it to the President again for signature. Recent Presidents and Congresses have disagreed about what constitutes an adjournment that prevents the return of a bill such that a pocket veto may be used. For purposes of the sections below concerning the use of veto threats, the unit of analysis is a veto. The analysis does not distinguish between regular and pocket vetoes. Because Congress faces a two-thirds majority threshold to override a President's veto, veto threats may deter Congress from passing legislation that the President opposes. The veto override threshold may also prompt Congress to change a bill in response to a veto threat. The Framers of the U.S. Constitution viewed the veto power as a way of reminding Congress that the President also plays an important legislative role and that threatening to use the veto power can influence legislators into creating more amenable bills. Political scientist Richard A. Watson writes that "the veto is available to a President as a general weapon in his conflicts with Congress: Franklin Roosevelt sometimes asked his aides for 'something I can veto' as a lesson and reminder to congressmen that they had to deal with a President." Veto threats are, therefore, an important component in understanding the use of the President's veto power. In recent presidencies, these threats have generally been expressed either through SAPs or verbally. President Trump has also used social media to communicate his intention to veto, oppose, or support a bill. Presidents may signal their intention to support, oppose, or veto a bill early in the legislative process using both verbal and written means. For example, Presidents can mention in a speech that they intend to veto legislation, or they can authorize others (such as a press secretary) to verbally indicate the Administration's position on specific legislation. Presidents can also issue, through the Office of Management and Budget (OMB), formal, written SAPs to communicate their intention to veto, oppose, or support a bill. Verbal veto threats may include commentary related to the President's strategy for working with Congress along with a threat to veto legislation if the President's policy agenda is not heeded. For example, at a press conference President George W. Bush explained, "I want the Members of Congress to hear that once we set a budget we're going to stick by it. And if not, I'm going to use the veto pen of the President of the United States to keep fiscal sanity in Washington, D.C." In another instance, President Obama said that the House "is trying to pass the most extreme and unworkable versions of a bill that they already know is going nowhere, that can't pass the Senate and that if it were to pass the Senate I would veto. They know it." In these remarks, both President Bush and President Obama used their words to attempt to deter Congress from passing bills that did not match the President's policy agenda and unambiguously remind the public of their veto power. Formal, written SAPs are frequently used to express the President's support for or opposition to particular pieces of legislation. The decision to issue a SAP is a means for the President to insert the Administration's views into the legislative debate. While SAPs provide Presidents an opportunity to assert varying levels of support for or against a bill, perhaps the most notable statement in a SAP is whether the Administration intends to veto the bill. Members of Congress may pay particular attention to a SAP when a veto threat is being made. At least one congressional leader has characterized SAPs as forerunner indicators of a veto. SAPs are often the first public document outlining the Administration's views on pending legislation and allow for the Administration to assert varying levels of support for or opposition to a bill. Because written threats are typically required to be scrutinized by the Administration through the central legislative clearance process in advance of their release, written SAP veto threats are often considered more formal than verbal veto threats. When a SAP indicates that the Administration may veto a bill, it appears in one of two ways: 1. A statement indicating that the President intends to veto the bill (hereinafter a presidential veto threat) or 2. A statement that agencies or senior advisors would recommend that the President veto the bill (hereinafter a senior advisors veto threat). These two types of SAPs indicate degrees of veto threat certainty. Generally speaking, a presidential veto threat signals the President's strong opposition to the bill. A senior advisors veto threat, on the other hand, may signal that the President may be more likely to enter into negotiations in order to reach a compromise with Congress on the bill. By publicly issuing a veto threat, the President may leverage public pressure upon Congress to support the President's agenda. Furthermore, many SAPs propose a compromise to Congress wherein the President would not exercise a veto. In addition, a President or an Administration's senior advisors may not always issue a veto threat prior to a decision to veto passed legislation. As discussed below, both Presidents Bush and Obama vetoed legislation for which they never issued a written veto threat. During both the Obama and Bush Administrations, roughly three-quarters of SAPs issued were on non-appropriations bills, and roughly one-quarter concerned appropriations bills. Each SAP signaled the Administration's intent to veto, oppose, or support a bill. There are fundamental differences between non-appropriations bill SAPs and appropriations bill SAPs. Non-appropriations bill SAPs typically involve specific policy objections, such as how a program operates or what constituency the program is designed to serve. Appropriations bill SAPs, in contrast, often involve more general budgetary policy objections, such as the perceived need to balance the budget or to reallocate resources for other purposes. Therefore, the President may generally support a particular provision in an appropriations bill on programmatic policy grounds but oppose it for budgetary reasons. Or the President may oppose a particular provision in an appropriations bill for both programmatic and budgetary reasons. This report focuses on the impact of the President's veto threat in non-appropriations bill SAPs given their more targeted nature. Data in this report were compiled from SAPs located on the archived White House websites of the Bush and Obama Administrations. Using the classification of SAPs on each website, analysis was conducted with only non-appropriations SAPs for reasons described above. The analysis examined each SAP and individually assessed whether the SAP contained a veto threat, the type of threat (presidential or senior advisor), and whether the veto threat concerned a part of the bill or the whole bill. The analysis considers each SAP to be an individual veto threat. In instances where one bill received veto threats in multiple SAPs, veto threats were counted individually and not combined. To assess the final outcome of bills, the analysis used information on bill statuses located at Congress.gov and does not track whether bills that received a SAP were later combined into other legislative vehicles. The inherent limitations in this methodology make it difficult to determine direct effects of any veto threat on the final outcome of a bill. However, in the aggregate, general trends may be observed. The proportion of non-appropriation bill SAPs with veto threats steadily increased over the course of each of the two presidencies reviewed. SAPs containing veto threats as a proportion of all SAPs was at its highest at the conclusion of both President Bush's and President Obama's second terms. Figure 1 illustrates this trend by showing SAP veto threats as a percentage of issued SAPs. While the Bush Administration remained relatively consistent in the number of veto threats issued in SAPs during its first six years, the number of threats increased during the final two years of the Administration. The Bush Administration issued a total of 491 SAPs on non-appropriations bills. Just under one-quarter (24%) of the non-appropriations bill SAPs contained a veto threat: 24 presidential veto threats and 94 senior advisors veto threats. Of bills that received a presidential veto threat, one was signed by the President, seven were vetoed, and the remaining 16 did not make it to the President's desk. Of bills that received a senior advisors veto threat, 16 were signed, one was vetoed, and the remaining 77 were not passed by both chambers. Seven of the 12 Bush Administration vetoes were preceded by a SAP containing a veto threat. While the number of veto threats in SAPs slowly increased during the first three Congresses of the Bush Administration (two in the 107 th Congress, three in the 108 th Congress, and seven in the 109 th Congress), the number of veto threats grew sharply in the 110 th Congressâto 107 veto threatsâcoinciding with Democrats gaining control of both chambers of Congress during the Republican President's final two years in office. This might suggest (and is supported by Obama Administration data) that the partisan constitution of Congress, as well as whether the Administration is in its first or second term, may impact the number of veto threats issued. Below, Figure 2 illustrates this change in the number of veto threats over time across the four Congresses associated with President Bush's two terms in office. Nevertheless, presidential veto threats in the Bush Administration remained a fraction of overall veto threats and often resulted in an actual veto. The rarity with which the Bush Administration issued presidential veto threats suggests that the Administration viewed them as a message to be used sparingly. Although the relationship between Congress and a President may change every two years with each new Congress, the relationship between an Administration and its President may also change by presidential term. Compared to a President's first term, in a second term Administration, executive branch officials may become more adept in coordinating the veto power. Additionally, a second-term President cannot be re-elected, which may allow the Administration to take a stronger position on unfavorable legislation. Alternatively, it could be that the President lacks the political influence necessary to advance his legislative agenda and instead relies on veto power to block legislative vehicles more often as his presidency concludes. Figure 3 presents veto threat percentages by presidential term for the Bush Administration, showing an increase in the President's second term. During President Bush's first term (2001-2005), 98% of SAPs did not contain a veto threat, 1% contained a senior advisors veto threat, and 1% contained a presidential veto threat. During President Bush's second term (2005-2009), 60% did not contain a veto threat, 32% contained a senior advisors veto threat, and 8% contained a presidential veto threat. In comparison to the Bush Administration, the Obama Administration steadily increased its use of veto threats issued in SAPs in every subsequent Congress. The Obama Administration issued 472 SAPs on non-appropriations bills. Just under half (48%) of these contained a veto threat: 43 presidential veto threats and 186 senior advisors veto threats. Of bills that received a presidential veto threat, four were ultimately signed by the President, five were vetoed, and 34 did not make it to the President's desk. Of bills that received a senior advisors veto threat, 17 were signed, two were vetoed, and 167 were not passed by the two chambers. Six of the 12 Obama Administration vetoes were preceded by a SAP containing a veto threat. President Obama (a Democrat) issued more veto threats in his SAPs with each passing Congress. (Democrats controlled both chambers during the 111 th Congress and the Senate during the 112 th Congress, and Republicans controlled the House during the 113 th Congress and both chambers during the 114 th Congress. ) Below, Figure 4 illustrates this change in the number of veto threats over time by Congress. Although the number of veto threats increased over the course of the Obama presidency (eight in the 111 th Congress, 54 in the 112 th Congress, 63 in the 113 th Congress, and 104 in the 114 th Congress), the number of presidential veto threats remained small when compared to the total number of veto threats, varying from a low of 14.3% in the 111 th Congress to a high of 28.3% in the 114 th Congress. The increase over time in total number of veto threats may indicate that President Obama was presented with more legislation he was likely to oppose. However, the increase is mostly composed of senior advisors veto threats. This suggests that the Administration nonetheless treated presidential veto threats, compared to senior advisors veto threats, as a tool to be used more rarely. As with the Bush Administration, President Obama's use of veto threats in the first and second terms differ. Figure 5 presents veto threat percentages by presidential term as opposed to by Congress. During President Obama's first term (2009-2013), 69% of SAPs did not contain a veto threat, 27% contained a senior advisors veto threat, and 4% contained a presidential veto threat. During President Obama's second term (2013-2017), 39% of SAPs did not contain a veto threat, 49% contained a senior advisors veto threat, and 13% contained a presidential veto threat. CRS analyzed all veto threats contained in SAPs on non-appropriations legislation across these two Administrations and determined whether the veto threat was isolated to a provision of the bill (a partial bill veto threat) or if the veto threat was not particularized (a whole bill veto threat). President Bush issued partial bill veto threats and whole bill veto threats an equal amount of the time. However, the type of threat he used in each category varied. Of partial bill veto threats, 7% were presidential veto threats and the remaining 93% were senior advisors veto threats. Of whole bill veto threats, 34% were presidential veto threats and the remaining 66% were senior advisors veto threats. In contrast, President Obama issued partial bill veto threats more sparingly (8% versus 92% for whole bill veto threats). Similar to President Bush, however, of partial bill veto threats, 6% were presidential veto threats and the remaining 94% were senior advisors veto threats. Of whole bill veto threats, 20% were presidential veto threats and the remaining 80% were senior advisors veto threats. The difference in frequency of partial and whole bill veto threats across the Administrations may suggest that the two Presidents viewed the use of veto threats differently: One President may have used partial threats to negotiate more with Congress, whereas another President preferred to threaten a veto only when he viewed an entire bill as unfavorable. Likewise, the increased frequency of partial bill senior advisors veto threats suggests that both Presidents preferred to use presidential veto threats in rejecting an entire bill and leaving senior advisors veto threats for negotiations where only part of a bill is unfavorable. A presidential veto threat in a SAP may be more likely than a senior advisors veto threat to deter passage of a bill because of the President's direct association with the threat. However, an analysis of these two Administrations does not necessarily support this argument. Figure 6 shows that bills appeared less likely to pass when the bill received a senior advisors veto threat versus a presidential veto threat. This may be due to a number of factors, including that senior advisors threats are more frequently issued than presidential veto threats (279 senior advisors threats and 67 presidential veto threats were issued across these two presidencies) or that Congress may perceive it to be beneficial to pass presidentially threatened legislation anyway based on certain political calculations and circumstances. During the Bush and Obama Administrations, enrolled bills that passed both chambers and were met with a presidential veto threat SAP were vetoed more often than were those that were met with a senior advisors threat. Figure 7 shows the outcomes of bills receiving veto threats that were passed by Congress and sent to the President. Across both the Bush and Obama Administrations, a bill that received a presidential veto threat and was passed was followed by a veto 70.6% of the time, whereas a bill that received a senior advisors veto threat was later vetoed 8.3% of the time. When a President vetoes a bill, it marks the end of the President's ability to procedurally affect whether or not a bill becomes law. Whether or not that specific bill becomes law is no longer in the President's hands. Congress may or may not elect to attempt an override. President Bush exercised the veto power 12 times. Four of these vetoes were overridden. Six vetoed bills were forewarned with a written veto threat. (Four received a presidential threat, and two received senior advisors threats.) Three additional bills received statements noting the Administration's opposition to the bill but did not include a veto threat. None of the bills that Congress later overrode were preceded by a presidential veto threat. Three-quarters of President Bush's vetoes (9 of 12) were preceded by a written statement of opposition to the bill. President Bush also issued multiple written veto threats on four bills that would later receive a veto: Three bills received two threats each, and one bill received two statements of opposition. President Obama vetoed 12 bills, and Congress overrode his veto once. As was true for President Bush, six of President Obama's vetoes were preceded by a written veto threat (four presidential and two senior advisors threats). Unlike the patterns observed for the Bush presidency, however, all of President Obama's veto threats were whole bill veto threats. Whereas President Bush also communicated in SAPs his opposition to three bills short of threatening a veto, President Obama either did not issue a SAP at all or issued one that contained a veto threat. One of President Obama's vetoed bills received two veto threats. President Obama's approach of issuing either no statement at all on a bill or a statement containing a veto threat marks a different approach from the one used by President Bush.

Summary: The Framers checked congressional legislative power by providing the President the power to veto legislation and, in turn, checked the President's veto power by providing Congress a means to override that veto. Over time, it has become clear that the presidential veto power, even if not formally exercised, provides the President some degree of influence over the legislative process. Most Presidents have exercised their veto power as a means to influence legislative outcomes. Of 45 Presidents, 37 have exercised their veto power. This report begins with a brief discussion of the ways Presidents communicate their intention to veto, oppose, or support a bill. It then examines the veto power and Congress's role in the veto process. The report then provides analysis of the use of veto threats and vetoes and the passage of legislation during the George W. Bush Administration (2001-2009) and the Obama Administration (2009-2017) with some observations of the potential influence of such actions on legislation. As specified by the U.S. Constitution (Article I, Section 7), the President has 10 days, Sundays excepted, to act once he has been presented with legislation that has passed both houses of Congress and either reject or accept the bill into law. The President has three general courses of action during the 10-day presentment period: The President may sign the legislation into law, take no action, or reject the legislation by exercising the office's veto authority. A President's return veto may be overridden, or invalidated, by a process also provided for in Article 1, Section 7, of the U.S. Constitution. Because Congress faces a two-thirds majority threshold to override a President's veto, veto threats may deter Congress from passing legislation that the President opposes. By going public with a veto threat, the President may leverage public pressure upon Congress to support his agenda. For purposes of this report, which focuses on the use of veto threats, the unit of analysis throughout is a veto (or a threatened veto), and the report does not distinguish between regular and pocket vetoes. Formal, written Statements of Administration Policy (SAPs, pronounced "saps") are frequently used to express the President's support for or opposition to particular pieces of legislation and may include statements threatening to use the veto power. Among the Bush and Obama Administrations' SAPs examined later in this report, for example, 24% and 48%, respectively, contained a veto threat. Although the relationship between Congress and a President may change every two years with each new Congress, the relationship between an Administration and its President may also change by presidential term. For example, while the number of veto threats in SAPs slowly increased during the first three Congresses of the Bush Administration, the number of veto threats grew sharply in the 110 th Congress. In comparison to the Bush Administration, the Obama Administration steadily increased its use of veto threats issued in SAPs in every subsequent Congress. President George W. Bush exercised the veto power 12 times during his presidency. Congress attempted to override six of President Bush's 12 vetoes and succeeded four times. President Barack Obama similarly exercised the veto power 12 times during his presidency. Congress also attempted to override six of President Obama's 12 vetoes and succeeded once. During the Bush and Obama Administrations, enrolled bills that passed both chambers and were met with a statement indicating that the President intended to veto the bill (a presidential veto threat SAP) were vetoed more often than were those that were met with a statement that agencies or senior advisors would recommend that the President veto the bill (a senior advisors threat SAP).