In his barnstormer of a speech to the swooning crowd at the Republican national convention on Wednesday night, Paul Ryan laid a mound of misdeeds at President Obama's door. To sustained applause from the floor, the vice-presidential candidate accused Obama of raiding Medicare, lying to auto workers and turning his back on the poor. But the speech (transcript here) was not always at pains to adhere to the historical record. At times, we are disappointed to report, Ryan baldly lied. Here's a round-up of Ryan's most audacious untruths:

Medicare

And the biggest, coldest power play of all in Obamacare came at the expense of the elderly … So they just took it all away from Medicare. Seven hundred and sixteen billion dollars, funneled out of Medicare by President Obama.

Barack Obama's budget plan calls for $716bn in cuts to Medicare spending over the next 10 years, but in reimbursements to insurers and hospitals, not in payments to beneficiaries, which would be preserved.

Ryan knows this because he has written these same cuts in to successive drafts of his famed budget. The cuts are designed to extend the solvency of Medicare for an estimated eight years. Repealing the cuts would likely increase payments by hundreds of dollars a year for beneficiaries, who share costs with the government.

Politifact has weighed in on Ryan's Medicare claim and found it to be "mostly false."

Ryan's hometown GM plant

Ryan said Obama held out false hope to workers in his hometown of Janesville, Wisconsin, that a GM plant there could be saved.

A lot of guys I went to high school with worked at that GM plant. Right there at that plant, Obama said: 'I believe that if our government is there to support you … this plant will be here for another hundred years.' That's what he said in 2008. Well, as it turned out, that plant didn't last another year.

Ryan accurately quotes Obama, who visited the plant as a presidential candidate in February 2008. Four months later, GM announced the plant would drastically scale back production. The plant laid off most of its workforce in December 2008, before Obama took office. The "government support" Obama spoke of – his auto bailout plan, which took effect in early 2009 – did not arrive early enough to save the Janesville plant, but it is credited with saving the American auto industry.

The full audacity of this attack cannot be appreciated without noting that Ryan's would-be boss, Mitt Romney, published an op-ed in the New York Times in November 2008 under the headline Let Detroit Go Bankrupt.

Government debt

[Obama] created a bipartisan debt commission. They came back with an urgent report. He thanked them, sent them on their way and then did exactly nothing.

In early 2010 Obama created a bipartisan committee known as Bowles-Simpson to figure out how to balance the budget and hand its recommendations to the president. The final draft of the committee's report failed to win the necessary support of its members, however, falling three votes short. Paul Ryan was on the committee, a fact that he neglected to mention in his speech. In the straw poll on the final draft, he voted "no" – against the plan that he now accuses the president of ignoring.

Aid to the poor

We have responsibilities, one to another – we do not each face the world alone. And the greatest of all responsibilities, is that of the strong to protect the weak. The truest measure of any society is how it treats those who cannot defend or care for themselves … We can make the safety net safe again.

If Paul Ryan's budget is notable for anything, it's for cuts to Medicaid and other programs on which low-income households depend. As the Washington Post economics blogger Ezra Klein points out: "The Center on Budget and Policy Priorities ran the numbers and said two-thirds of Ryan's cuts will end up falling on programs for the poor."

The Ryan plan cuts spending on Medicaid and other health assistance programs for the poor from just over 3% of GDP to just over 1%. It cuts home mortgage deductions, veteran's benefits, farm subsidies and other aid programs.

Credit rating downgrade

Ryan said the president was responsible for Standard and Poor's downgrading US credit from AAA to AA+ in August 2011. He said of Obama's first term:

It began with a perfect Triple-A credit rating for the United States; it ends with a downgraded America.

In fact, the downgrade was the result of refusal of Republicans in Congress to vote to raise the debt ceiling, despite pressure from the White House and most outside analysts.

So stubborn was the Republican resistance that treasury secretary Timothy Geithner suggested the president could unilaterally raise the ceiling under the 14th amendment. Ultimately the Republicans capitulated, but the damage was done; days after the Budget Control Act of 2011 was signed, the rating was cut.

In its statement on the rationale behind the downgrade, Standard and Poor's blamed the political circus: "The political brinksmanship of recent months highlights what we see as America's governance and policymaking becoming less stable, less effective, and less predictable than what we previously believed."