After being sworn in as attorney general, Swanson filed a series of lawsuits against life insurance companies that sold unsuitable annuities to senior citizens.

[14] As Swanson took office, the country was beginning to face a housing crisis and eventual recession spurred by predatory subprime mortgage lending.

Before she took office, Swanson announced a predatory lending working group to make recommendations to legislators for reforming abuses in the mortgage industry.

[29] In January 2012, Swanson sued Accretive Health, a billing and revenue consulting firm hired by two Twin Cities hospitals, for losing patient data on a lap top.

In April 2012, the lawsuit again expanded when Swanson alleged that Accretive embedded bill collectors in the emergency rooms of hospitals and demanded payment by patients before and during treatment.

[42] In July, 2017 the Minnesota Supreme Court found in Swanson's lawsuit that the school made illegal usurious loans to students at interest rates as high as 18 percent.

[44] In 2014, Swanson issued a scathing report on charities that contract with Savers, Inc., a for profit company that collects and sells second hand clothing through the United States and Canada.

[50] In September 2016, Swanson sued Indivior PLC, a manufacturer of the opioid withdrawal medicine Suboxone, for unlawfully keeping out generic competition by tweaking the drug's structure to obtain a separate patent.

[51] She also wrote to insurance companies that month asking them to remove pre-authorization approval barriers to prevent or delay patients from getting access to opioid withdrawal treatment.

[52] In November 2016, Swanson issued a report on the opioid epidemic, calling for legislative and regulatory reforms as it relates to protocols on prescribing pain killers.

In 2009, she filed a lawsuit against a major hospital system for charging 18 percent interest on unpaid medical bills in violation of Minnesota usury laws.

[66] In 2007, 2012, and 2017, she renewed agreements first reached by her predecessor in 2005 with all Minnesota hospitals to reform the manner in which they collect unpaid medical bills and charge uninsured patients.

[75] In 2017 Swanson intervened after the state's largest insurance company and children's hospital failed to agreeing on a contract, bringing the two chief executive officers together to help forge a solution that would ensure continuity of care for 60,000 child patients.

She brought the first lawsuit by a regulator in the country against one of the nation's largest collection agencies for “robo-signing” thousands of legal documents without verifying their accuracy.

In a settlement with Swanson's office, the company agreed to reform its practices and substantiate that debts were owed before filing collection lawsuits.

[79] Swanson later got enacted bipartisan legislation that required debt buyers to provide evidence they are targeting the correct person in the right amount before filing collection lawsuits.

[80] Swanson also got millions of dollars of bills written off after suing a Minnesota collection company that added 22 percent interest to old bank overdraft fees.

[81] In 2017, she sued an outfit that got senior citizens to sign over large portions of their future pensions at high costs for military benefits in exchange for small loans.

[82] Starting in 2011, Swanson filed suit against many online “payday” lenders for making high-cost unlicensed loans to Minnesota residents, winning an $11 million settlement against one such company in 2016.

[84] On February 1, 2017, Swanson joined the attorneys general of the states of Washington, New York, Virginia, and Massachusetts in bringing a lawsuit against the administration of President Donald Trump.

The suit challenged the president's executive order that bans refugees and travelers from a list of predominantly Muslim nations from entering the United States.

"[86] In February 2018, Swanson reached a settlement of a major environmental lawsuit she filed in 2010 against 3M Company over its disposal of chemicals for several decades into the drinking water in the east metropolitan area of the Twin Cities.

The Drum Major Institute of New York designated Swanson's predatory mortgage legislation on one of the ten top public policies proposed in 2008.