Before getting to the opinion of the group ‘Cause of Action’, allow me to just highlight the trail and how it appears to be falling into place.

January 2010 – President Obama gives a state of the union speech where he decries the recent Supreme Court ruling “Citizens United”.  (video here)  I’m also going to put the video below and make an odd request:
Please, watch it 5 to 8 times!   At each time look at the key people who react and/or rise after Obama’s words.   Most have noted Supreme Court Justice Sam Alito’s infamous mouthing of the words “that’s not true“, but I need you to look beyond Alito and the unknown Supreme court Senior aide {female at end of row}.

Look at Treasury Sec Tim Geithner and Attorney General Eric Holder.  Then replay and look at Senator Harry Reid, Senator Dick Durban and Senator Chuck Schumer {seated behind the Supremes}.   Pictures and video are worth thousands of words.
SUMMER 2010 –  In 2014 hindsight we know after this State of Union Speech – The IRS Tax Head Lois Lerner and the DOJ are in discussions about whether the Tax Enforcement Unit inside the DOJ should be assisting the IRS with investigation, using the FBI, of 501(c)(4) entities that are specifically the ire of the Obama administration as a result of that Citizens United ruling. 
SUMMER 2010 – As a result of those IRS and DOJ meetings Lois Lerner sends 21 CD-ROM’s (1.1 million pages) of tax information to the DOJ/FBI for their use.   Included in the data sent was 33 different full tax return filing’s of 501(c)(4) organizations adverse to the administration.
We also know that inside that data set Lerner sent the DOJ  were 33 “Schedule B” filings (illegal to distribute).   Those “schedule B’s” outlined every person, organization and entity who supported the 501(c)(4)’s.
On October 19, 2010, Lerner spoke at an event sponsored by Duke University’s Sanford School of Public Policy.  At the event, Lerner referenced the political pressure the IRS faced to “fix the problem” of 501(c)(4) groups engaging in political activity.   She stated:

What happened last year was the Supreme Court – the law kept getting chipped away, chipped away in the federal election arena.  The Supreme Court dealt a huge blow, overturning a 100-year old precedent that basically corporations couldn’t give directly to political campaigns.  And everyone is up in arms because they don’t like it.  The Federal Election Commission can’t do anything about it.

They want the IRS to fix the problem.  The IRS laws are not set up to fix the problem:  (c)(4)s can do straight political activity.  They can go out and pay for an ad that says, “Vote for Joe Blow.”  That’s something they can do as long as their primary activity is their (c)(4) activity, which is social welfare.

So everybody is screaming at us right now:  ‘Fix it now before the election.  Can’t you see how much these people are spending?’  I won’t know until I look at their 990s next year whether they have done more than their primary activity as political or not.  So I can’t do anything right now.

Who’s “their” ?
… possibly the 33 Groups outlined whose filings were illegally sent to the FBI and whose tax filing included a list made possible through the “Schedule B’s” ?
I think so.
NOVEMBER 2010 – MID TERM ELECTION:  Democrats were “shellacked”!

Obama concedes ‘shellacking’ – Blames process, not his policies, for Democrats’ setback. (link)

You can imagine against the intensity backdrop around ‘Citizens United’ what the environment would have been like inside the IRS / FEC / DOJ political machine
FALL 2010 Through June 2011 –   We now know as a result of feedback sent by people and organizations (quite possibly all listed on those, illegally distributed, 33 Schedule B’s) to congress – the House Ways and Means Committee began to hear evidence that suggested targeting.
JUNE 3rd, 2011 –  Chairman Dave Camp sent Lois Lerner a letter inquiring about what activity the IRS was engaged upon that would be causing delays and additional inquiry from the IRS into “conservative groups” who were complaining to his committee.   Camp asked for a response from Lerner’s office.
JUNE 13th, 2011 – Ten days after Chariman Camp’s letter arrives at the IRS, Lois Lerner’s email system has a mysterious malfunction.  Her hard drive also mysteriously crashes, supposedly wiping out the communication trail for what activity she was engaged upon with entities outside the IRS offices.

It does not take a super sleuth to identify what that timeline reflects !

May 10th 2013 – IRS Admits to targeting Conservative groups and 501(c)(4) groups opposed to the Obama administration.  By planting question amid reporters.
May 14th  2013 – Inspector General Report shows “ineffective IRS management” allowed targeting to occur.   I would argue the word “ineffective” be replaced with “intentional“.
May 22nd 2013 – Lois Lerner pleads the Fifth
June 27th 2014 – Last WEEK: Lois Lerner attorney claims his client, in 2010, 2011, 2012, was only responding to requests from the DOJ/FBI and was not soliciting them for action.  Claims they were the ones asking Lerner for the information (link)
July 2nd 2014, IRS General Counsel responds to inquiry from Trey Gowdy:

Here’s the latest: 

WASHINGTON DC – New evidence about Lois Lerner’s missing emails suggests IRS acted in “bad faith,” and that there may have been White House involvement.
Cause of Action, a watchdog group that is investigating embattled former IRS official Lois Lerner, believes that there’s strong evidence proving the tax agency has obstructed Congress by losing Lerner’s emails and has suggested steps to get to the bottom of the situation.
According to a statement released to The Daily Caller by Cause of Action, the government watchdog group believes that there is evidence suggesting the IRS acted in “bad faith” in the case of the missing emails and that there might’ve been involvement with the White House in this action.
Cause of Action filed a FOIA request — along with Tea Party Patriots — seeking answers as to whether the IRS broke the law when it lost Lerner’s emails on June 24.
Dan Epstein, executive director for Cause of Action, outlined how this is the case in an interview with TheDC where he stated that the day (June 3, 2011) when Rep. Dave Camp, chairman of the House Ways and Means Committee, sent a letter to the IRS asking questions about the targeting of conservative groups is the date where the investigation began and when the IRS should’ve been well prepared for preserving Lerner’s hard drive.
“It’s very clear that this is obstruction of Congress,” Epstein told TheDC. “The IRS on June 3, 2011 became on notice that there was a congressional investigation, which automatically means that there is a duty to preserve documents.”
“There should’ve been copies of Lois Lerner’s hard drive and there should’ve been other practices to make sure all of her emails and documents were preserved,” Epstein continued. “It’s very clear from the record that there was no such hold of Lois Lerner’s documents at the time that Congressman Camp sent that June 3, 2011 letter.”
“There should be an inference of bad faith — they [Congress] can say that this was a bad faith loss of records, it was actually destruction, it was actually intentional.”  (read more)