Mryntu

The two main issues investigated by Mueller with regard to Trump seem to be conspiracy and obstruction of justice.

We already have a question here which deals with the conspiracy issue.

What about obstruction? How many cases of obstruction by Trump or his campaign are described in the Mueller report, which of these are new information, and what is the given evidence?

Interpretation by PBS

I have found a list similar to the one posted by Fizz, the list is compiled by PBS and contains eleven 'moments Mueller investigated for obstruction of justice'. In addition to the list posted by Fizz, PBS also mentions:

• What Trump knew and what he denied about Russia and WikiLeaks (pages 228-236).




• Did the president try to cover up Michael Flynn’s phone calls with the Russian ambassador or protect him from prosecution? (pages 237-259)




• Trump’s repeated urging of top administration officials to deny he was under investigation (pages 260- 273)

Directly from the Mueller report

Given the discrepancies between those lists, it might be worth looking at what the Mueller report itself says about the matter. Luckily, the Mueller report summarises just that in the first part of the executive summary to volume II, titled Factual Results of the Obstruction Investigation. The key issues and events (starting on page 3 of the second volume, page 215 in the linked pdf) as stated in that summary are posted below.

For each of the counts, I will add the full explanation from the summary. Initially, I tried to quote a sentence (or two) to condense it a bit further but that's basically cherry-picking as everything in the summary is already written in as few words as can be. I added extra line breaks where appropriate.

Factual Results of the Obstruction Investigation

The key issues and events we examined include the following:

1. 
   

   The Campaign’s response to reports about Russian support for Trump

   
   
   
   • During the 2016
     about any further planned WikiLeaks
     presidential campaign, questions arose about the Russian government’s apparent support for
     candidate Trump. After WikiLeaks released politically damaging Democratic Party emails that
     were reported to have been hacked by Russia, Trump publicly expressed skepticism that Russia
     was responsible for the hacks at the same time that he and other Campaign officials privately
     sought information [redacted; harm to ongoing matter]
     releases.
     
     Trump also denied having any business in or connections to Russia, even though as late
     as June 2016 the Trump Organization had been pursuing a licensing deal for a skyscraper to be
     built in Russia called Trump Tower Moscow. After the election, the President expressed concerns
     to advisors that reports of Russia’s election interference might lead the public to question the
     legitimacy of his election.
   
   


2. 
   

   Conduct involving FBI Director Comey and Michael Flynn.

   
   
   
   • In mid-January 2017,
     incoming National Security Advisor Michael Flynn falsely denied to the Vice President, other
     administration officials, and FBI agents that he had talked to Russian Ambassador Sergey Kislyak
     about Russia’s response to U.S. sanctions on Russia for its election interference. On January 27,
     the day after the President was told that Flynn had lied to the Vice President and had made similar
     statements to the FBI, the President invited FBI Director Comey to a private dinner at the White
     House and told Comey that he needed loyalty. On February 14, the day after the President
     requested Flynn’s resignation, the President told an outside advisor,
     “Now that we fired Flynn, the
     Russia thing is over.
     ” The advisor disagreed and said the investigations would continue.
     
     
     
     Later that afternoon, the President cleared the Oval Office to have a one-on-one meeting
     with Comey. Referring to the FBI’s investigation of Flynn, the President said,
     “I hope you can
     see your way clear to letting this go, to letting Flynn go. He is a good guy. I hope you can let this
     go.” Shortly after requesting Flynn’s resignation and speaking privately to Comey, the President
     sought to have Deputy National Security Advisor K.T. McFarland draft an internal letter stating
     that the President had not directed Flynn to discuss sanctions with Kislyak. McFarland declined
     because she did not know whether that was true, and a White House Counsel’s Office attorney
     thought that the request would look like a quid pro quo for an ambassadorship she had been offered.
   
   


3. 
   

   The President’s reaction to the continuing Russia investigation.

   
   
   
   • In February 2017,
     Attorney General Jeff Sessions began to assess whether he had to recuse himself from campaign-related investigations because of his role in the Trump Campaign. In early March, the President
     told White House Counsel Donald McGahn to stop Sessions from recusing. And after Sessions
     announced his recusal on March 2, the President expressed anger at the decision and told advisors
     that he should have an Attorney General who would protect him. That weekend, the President
     took Sessions aside at an event and urged him to “unrecuse.”
     
     
     Later in March, Comey publicly disclosed at a congressional hearing that the FBI was investigating “the Russian government’s
     efforts to interfere in the 2016 presidential election,” including any links or coordination between
     the Russian government and the Trump Campaign.
     
     In the following days, the President reached
     out to the Director of National Intelligence and the leaders of the Central Intelligence Agency
     (CIA) and the National Security Agency (NSA) to ask them what they could do to publicly dispel
     the suggestion that the President had any connection to the Russian election-interference effort.
     The President also twice called Comey directly, notwithstanding guidance from McGahn to avoid
     direct contacts with the Department of Justice. Comey had previously assured the President that
     the FBI was not investigating him personally, and the President asked Comey to “lift the cloud”
     of the Russia investigation by saying that publicly.
   
   


4. 
   

   The President’s termination of Comey.

   
   
   
   • On May 3, 2017, Comey testified in a
     congressional hearing, but declined to answer questions about whether the President was
     personally under investigation. Within days, the President decided to terminate Comey. The
     President insisted that the termination letter, which was written for public release, state that Comey
     had informed the President that he was not under investigation. The day of the firing, the White
     House maintained that Comey’s termination resulted from independent recommendations from the
     Attorney General and Deputy Attorney General that Comey should be discharged for mishandling
     the Hillary Clinton email investigation.
     
     But the President had decided to fire Comey before
     hearing from the Department of Justice. The day after firing Comey, the President told Russian
     officials that he had “faced great pressure because of Russia,
     ” which had been “taken off’ by
     Comey’s firing. The next day, the President acknowledged in a television interview that he was
     going to fire Comey regardless of the Department of Justice’s recommendation and that when he
     “decided to just do it,
     ” he was thinking that “this thing with Trump and Russia is a made-up story.
     ”
     In response to a question about whether he was angry with Comey about the Russia investigation,
     the President said,
     “As far as I’m concerned, I want that thing to be absolutely done properly,
     ”
     adding that firing Comey “might even lengthen out the investigation.
     ”
   
   


5. 
   

   The appointment of a Special Counsel and efforts to remove him.

   
   
   
   • On May 17, 2017, the
     Acting Attorney General for the Russia investigation appointed a Special Counsel to conduct the
     investigation and related matters. The President reacted to news that a Special Counsel had been
     appointed by telling advisors that it was “the end of his presidency” and demanding that Sessions
     resign. Sessions submitted his resignation, but the President ultimately did not accept it. The
     President told aides that the Special Counsel had conflicts of interest and suggested that the Special
     Counsel therefore could not serve. The President’s advisors told him the asserted conflicts were
     meritless and had already been considered by the Department of Justice.
     
     
     On June 14, 2017, the media reported that the Special Counsel’s Office was investigating
     whether the President had obstructed justice. Press reports called this “a major turning point” in
     the investigation: while Comey had told the President he was not under investigation, following
     Comey’s firing, the President now was under investigation. The President reacted to this news
     with a series of tweets criticizing the Department of Justice and the Special Counsel’s
     investigation. On June 17, 2017, the President called McGahn at home and directed him to call
     the Acting Attorney General and say that the Special Counsel had conflicts of interest and must be
     removed. McGahn did not carry out the direction, however, deciding that he would resign rather
     than trigger what he regarded as a potential Saturday Night Massacre.
   
   


6. 
   

   Efforts to curtail the Special Counsel's investigation.

   
   
   
   • Two days after directing McGahn
     to have the Special Counsel removed, the President made another attempt to affect the course of
     the Russia investigation. On June 19, 2017, the President met one-on-one in the Oval Office with
     his former campaign manager Corey Lewandowski, a trusted advisor outside the government, and
     dictated a message for Lewandowski to deliver to Sessions. The message said that Sessions should
     publicly announce that, notwithstanding his recusal from the Russia investigation, the investigation
     was “very unfair” to the President, the President had done nothing wrong, and Sessions planned to
     meet with the Special Counsel and “let [him] move forward with investigating election meddling
     for future elections.
     ” Lewandowski said he understood what the President wanted Sessions to do.
     
     
     One month later, in another private meeting with Lewandowski on July 19, 2017, the
     President asked about the status of his message for Sessions to limit the Special Counsel
     investigation to future election interference. Lewandowski told the President that the message
     would be delivered soon. Hours after that meeting, the President publicly criticized Sessions in an
     interview with the New York Times, and then issued a series of tweets making it clear that
     Sessions’s job was in jeopardy. Lewandowski did not want to deliver the President’s message
     personally, so he asked senior White House official Rick Dearborn to deliver it to Sessions.
     Dearborn was uncomfortable with the task and did not follow through.
   
   


7. 
   

   Efforts to prevent public disclosure of evidence.

   
   
   
   • In the summer of 2017, the President
     learned that media outlets were asking questions about the June 9, 2016 meeting at Trump Tower
     between senior campaign officials, including Donald Trump Jr., and a Russian lawyer who was
     said to be offering damaging information about Hillary Clinton as “part of Russia and its
     government’s support for Mr. Trump.
     
     
     ” On several occasions, the President directed aides not to
     publicly disclose the emails setting up the June 9 meeting, suggesting that the emails would not
     leak and that the number of lawyers with access to them should be limited. Before the emails
     became public, the President edited a press statement for Trump Jr. by deleting a line that
     acknowledged that the meeting was with “an individual who [Trump Jr.] was told might have
     information helpful to the campaign” and instead said only that the meeting was about adoptions
     of Russian children. When the press asked questions about the President’s involvement in Trump
     Jr.
     ’s statement, the President’s personal lawyer repeatedly denied the President had played any
     role.
   
   


8. 
   

   Further efforts to have the Attorney General take control of the investigation.

   
   
   
   • In early
     summer 2017, the President called Sessions at home and again asked him to reverse his recusal
     from the Russia investigation. Sessions did not reverse his recusal. In October 2017, the President
     met privately with Sessions in the Oval Office and asked him to “take [a] look” at investigating
     Clinton. In December 2017, shortly after Flynn pleaded guilty pursuant to a cooperation
     agreement, the President met with Sessions in the Oval Office and suggested, according to notes
     taken by a senior advisor, that if Sessions unrecused and took back supervision of the Russia
     investigation, he would be a “hero.
     ” The President told Sessions,
     “I’m not going to do anything
     or direct you to do anything. I just want to be treated fairly.
     ” In response, Sessions volunteered
     that he had never seen anything “improper” on the campaign and told the President there was a
     “whole new leadership team” in place. He did not unrecuse.
   
   


9. 
   

   Efforts to have McGahn deny that the President had ordered him to have the Special
   Counsel removed.

   
   
   
   • In early 2018, the press reported that the President had directed McGahn to have the Special Counsel removed in June 2017 and that McGahn had threatened to resign rather
     than carry out the order. The President reacted to the news stories by directing White House
     officials to tell McGahn to dispute the story and create a record stating he had not been ordered to
     have the Special Counsel removed. McGahn told those officials that the media reports were
     accurate in stating that the President had directed McGahn to have the Special Counsel removed.
     The President then met with McGahn in the Oval Office and again pressured him to deny the
     reports. In the same meeting, the President also asked McGahn why he had told the Special
     Counsel about the President’s effort to remove the Special Counsel and why McGahn took notes
     of his conversations with the President. McGahn refused to back away from what he remembered
     happening and perceived the President to be testing his mettle.
   
   


10. 
    

    Conduct towards Flynn, Manafort, [redacted; HOM].

    
    
    
    • After Flynn withdrew from a joint defense
      agreement with the President and began cooperating with the government, the President’s personal
      counsel left a message for Flynn’s attorneys reminding them of the President’s warm feelings
      towards Flynn, which he said “still remains,
      ” and asking for a “heads up” if Flynn knew
      “information that implicates the President.
      ” When Flynn’s counsel reiterated that Flynn could no
      longer share information pursuant to a joint defense agreement, the President’s personal counsel
      said he would make sure that the President knew that Flynn’s actions reflected “hostility” towards
      the President.
      
      During Manafort’s prosecution and when the jury in his criminal, trial was
      deliberating, the President praised Manafort in public, said that Manafort was being treated
      unfairly, and declined to rule out a pardon. After Manafort was convicted, the President called
      Manafort “a brave man” for refusing to “break” and said that “flipping” “almost ought to be outlawed.” [large redaction; harm to ongoing matter]
    
    


11. 
    

    Conduct involving Michael Cohen.

    
    
    
    • The President’s conduct towards Michael Cohen, a
      former Trump Organization executive, changed from praise for Cohen when he falsely minimized
      the President’s involvement in the Trump Tower Moscow project, to castigation of Cohen when
      he became a cooperating witness.
      
      From September 2015 to June 2016, Cohen had pursued the
      Trump Tower Moscow project on behalf of the Trump Organization and had briefed candidate
      Trump on the project numerous times, including discussing whether Trump should travel to Russia
      to advance the deal.
      
      In 2017, Cohen provided false testimony to Congress about the project,
      including stating that he had only briefed Trump on the project three times and never discussed
      travel to Russia with him, in an effort to adhere to a “party line” that Cohen said was developed to
      minimize the President’s connections to Russia. While preparing for his congressional testimony,
      Cohen had extensive discussions with the President’s personal counsel, who, according to Cohen,
      said that Cohen should “stay on message” and not contradict the President.
      
      After the FBI searched
      Cohen’s home and office in April 2018, the President publicly asserted that Cohen would not
      “flip,
      ” contacted him directly to tell him to “stay strong,
      ” and privately passed messages of support
      to him. Cohen also discussed pardons with the President’s personal counsel and believed that if
      he stayed on message he would be taken care of. But after Cohen began cooperating with the
      government in the summer of 2018, the President publicly criticized him, called him a “rat,
      ” and
      suggested that his family members had committed crimes.
    
    

Why the president wasn't prosecuted for obstruction of justice

In reply to your comment under Fizz's answer:

As far as I understand, Mueller didn't indict Trump because he didn't think that he had the authority to do so, not because he didn't see cases of obstruction.

The executive summary ends with the following conclusion (on page 8 of the second volume, page 220 in the linked pdf):

Conclusion

Because we determined not to make a traditional prosecutorial judgment, we did not draw
ultimate conclusions about the President’s conduct. The evidence we obtained about the
President’s actions and intent presents difficult issues that would need to be resolved if we were
making a traditional prosecutorial judgment. At the same time, if we had confidence after a
thorough investigation of the facts that the President clearly did not commit obstruction of justice,
we would so state. Based on the facts and the applicable legal standards, we are unable to reach
that judgment. Accordingly, while this report does not conclude that the President committed a
crime, it also does not exonerate him.

Note that pages 7 and 8 of the second volume go into more detail when it comes to the decision not to prosecute the president for obstruction of justice, but I think the conclusion suffices here.

If you want to be technical about it, zero "cases of obstruction", since Mueller didn't indict Trump. On the other hand, a lot of legal commentators have concluded that what Mueller wrote is a roadmap to Trump's impeachment; I won't include quotes on that here, because it doesn't seem to the main issue.

I know what you're probably thinking about in terms of an anwer (since you put "potential" in your title): that Trump attempted to have various underlings obstruct justice, but since they had qualms about it... E.g. BBC's quick summary:

Mr Mueller examined 10 actions by the president in regards to obstruction of justice, which he said largely "took place in public view".

The report says that potential obstruction of justice by the president only failed because members of his administration refused to "carry out orders".

And of course legal experts as splicing the report five ways to heaven, so you pick can your favorite interpretation thereof. Never mind the pundits and politicians.

Below is the list of those 10 issues, as summarized by Global News each with the "verdict" of Mueller as interpreted by Patrick J. Cotter, a former New York state and federal prosecutor:

Here are the 10 episodes Mueller looked at and how he appeared to evaluate each one, according to Cotter’s analysis.

1. Pressuring Comey to let Flynn go (unlikely)


2. Trying to stop Jeff Sessions from recusing himself in the Russia investigation (likely)


3. Firing James Comey (likely)


4. Trying to fire Mueller (likely)


5. Trying to limit the scope of Mueller’s investigation (unclear)


6. Trying to hide emails about Trump Jr.’s meeting with Russians at Trump Tower (unlikely)


7. Trying to get Sessions to step in after recusing himself from the Mueller probe (likely)


8. Telling Don McGhan to publicly deny that Trump tried to fire Mueller (likely)


9. Sympathetic comments toward Flynn, Manafort and other possible witnesses (likely)


10. Attacking Michael Cohen (unclear)

Also the Democrats have subpoenaed the full report because about 10% of it is redacted.

The Economist's commentary is sufficient for though:

Mr Mueller’s report [says] “Congress has authority,” he wrote, “to prohibit a president’s corrupt use of his authority…The conclusion that Congress may apply the obstruction laws to the president’s corrupt exercise of the powers of office accords with our constitutional system of checks and balances and the principle that no person is above the law.”

It seems unlikely that Congress will do so: the Democratic leadership in the House has sensibly concluded that impeachment proceedings could backfire politically. There is nothing in the new report that will suddenly persuade Republicans in the Senate to abandon the president. It is nonetheless an extraordinary document.

As for new info in the Mueller report regarding potential obstruction, according to CNN, this bit was new:

Mueller also described a previously unknown example of the President's attempts to curtail the investigation involving Trump's former campaign manager Corey Lewandowski.

The report says that on June 19, 2017, Trump met in the Oval Office with Lewandowski and dictated a message intended for then-Attorney General Jeff Sessions, who at that point had recused himself from matters involving the probe.

In the message, Sessions was told to publicly announce the investigation was "'very unfair' to the President, the President had done nothing wrong, and Sessions planned to meet with the special counsel and 'let [him] move forward with investigating election meddling for future elections.'" Lewandowski told Trump he understood his instructions.

Ultimately, Lewandowski declined to deliver the message personally, instead asking a senior White House official -- deputy chief of staff Rick Dearborn -- to do it instead. Mueller's report says Dearborn was "uncomfortable with the task and did not follow through."

Slate also called that Lewandowski info new and adds the following "juicy detail" (their term) as also new

while we knew Trump directed White House Counsel Don McGahn to tell Rod Rosenstein to fire Mueller, we didn’t know the president had called McGahn at home to pressure him. McGahn told his chief of staff Annie Donaldson that the president called at least twice and at one point asked, “Have you done it?” McGahn told the president’s then–chief of staff Reince Priebus that Trump had asked him to “do crazy shit.”

Frankly in quite a few other countries (in Europe but not only), the would be outrage at political [attempts] at interferece in prosecutorial decisions, even if it doesn't ammount to obstruction of justice. But I guess this [former] standard of the independece of prosecutors doesn't exist in the US.

The Venice Commission goes on to refer to two different but related abuses, the first being the
bringing of prosecutions which ought not to be brought, and the second, which the Commission
describes as more insidious and probably commoner, being the failure of the prosecutor to bring a
prosecution which ought to be brought. The Commission points out that this problem is frequently
associated with corruption but may also be encountered where governments have behaved in a
criminal or corrupt manner or where powerful interests bring political pressure to bear. The report
points out that in principle a wrong instruction not to prosecute may be more difficult to counter
because it may not easily be made subject to judicial control. The possibility of giving victims a
right to seek a judicial review of cases of non-prosecution is referred to.
The conclusion which can be drawn from these comments is that independence of the prosecutor
does not exist as a value in itself but rather as a means of preventing improper political or other
interference in the work of the prosecutor and ensuring that prosecutorial decisions, so far as
possible, are made fairly and impartially, just as a judge is expected to act fairly and impartially
without being subject to outside pressures.