The deputy told McFarland they could take him to the hospital by ambulance, but McFarland refused because he couldn't afford it.
Despite his wife's objections, deputies kept the taser trained on him and ordered him to get in an ambulance:
Deputy: We can take you by ambulance, we told you that.
McFarland: I can't afford it.
McFarland's Wife: He has a heart problem.
Deputy: Put your hands behind your back.
McFarland: F*ck you.
Deputy tases McFarland.
Deputy: Stop resisting, stop resisting…or I'll give it to you again.
The deputy shocks McFarland several times while continuing to tell him to stop resisting.
This is the latest incident to raise controversy over the use of tasers, which police departments claim can reduce injuries and fatalities. But a study of major U.S. cities, found deaths in-custody actually rise sharply - nearly six times - during the first year a department uses tasers. Dr. Byron Lee of the University of California at San Francisco led the study.
After the first year in-custody deaths returned to the same level as before tasers were introduced. Tasers are now used by more than 12,000 law enforcement agencies.
By 2008, a study by Amnesty International showed in at least 35 states there were deaths after tasers were in use. 55 in California and 52 in Florida.
Experts say the risk of deaths increases when a person is shocked with a taser more than once Peter McFarland was hit four times.
"What I saw in (the McFarland video of the tasering) was a non-life threatening situation turned into a life threatening one," said Dr. Lee.
"All of a sudden they just showed up," said McFarland. "And they came in her like there was a fire going on, or some gunfight was going on."
McFarland is now suing the Marin County California Sheriff's Department, which says its deputies were following the law and department policy.