Few questions appeared until Wednesday afternoon when responses started piling in. Some users simply made fun of the bank's attempt to use social media, but many others chose to insult executives or ask barbed questions about bank's recent legal problems and corporate responsibility.
"Reading the #AskJPM Twitter feed makes it seem JPM put a 'kick me' sticker on its back when it rolled out that hashtag," wrote a user who identified himself as an editor and columnist.
A woman who said she was a community organizer and "next gen freedom fighter" asked if Lee, a vice-chairman and deal rainmaker at the bank, thought it was "ok to outright lie, cheat and steal."
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A woman called Charlotte mocked the bank's attempt at social media outreach as an "epic derailment" and asked: "Is it true that, while you don't always spit on poor people, when you do, you have perfect aim?"
A blogger and online journalist asked about the scale of the bank's alleged wrongdoing in electric energy trading compared with that in its sales of mortgage securities. Another user known as "Guerrilla Educator" asked if anyone in Lee's family had ever been foreclosed upon.
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The company's tweets last week said Lee had been part of Wall Street's biggest deals and had worked with Dell Inc and General Motors. The tweets said Lee would "answer your questions on leadership and life." JPMorgan was an underwriter of Twitter's recent initial public offering of stock.
In an effort to boost their relationship with customers, a growing number of companies are putting their executives in the line of fire by hosting highly publicized Q&As. All too often, however, they backfire. JPMorgan is by no means the first.
U.K. budget airline Ryanair's outspoken CEO, Michael O'Leary, sparked controversy when he took to Twitter in October to answer customers' questions using the hashtag #GrillMOL.
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But his tweets - which included a number of references to the attractiveness of female correspondents – were met with disbelief by some customers.
Ryanair's Q&A followed an attempt by British Gas to win customers round on the same day it announced price rises of over 9 percent – a move that surprised a number of Twitter users.
-Reuters contributed to this story.