No, they, and he cannot.
Gary Johnson personally promised to pardon husband and wife Libertarian activists Gary and Karen "Kay" Fincher for the non-crime "offense" they were convicted of. They were arrested by thug police outside of a polling place on election day for wearing pro-Libertarian buttons and T-shirts, and charged with "Electioneering." The arrest took place after Kay covered up the button she was wearing, so it was a vindictive false arrest. While Johnson was still governor, Fincher showed up to a Massachusetts Libertarian Party convention, and confronted Johnson about their conviction, showing him a newspaper clipping detailing the entire affair. Johnson reacted with shock, and promised to pardon them, but his protective ring of suck-ups never allowed them to get through to him, even though he promised to make himself personally available to them. Johnson left office without pardoning them, and Kay died of cancer, without ever having been pardoned. You can read all about it,here.
The entire account is truthful, and even though Fincher is not my favorite person in the world (I know him personally), the information he provides on his blog is 100% true.
Johnson has lied about how many people he pardoned, many times. He always "gives himself an out" by qualifying the statement "I may have" and giving an inexact number. It's always politician-talk, pure bullshit. As near as I can tell, he pardoned around 148 people.
Here's a link to Johnson's own defense of his positions, and rather than finding it exculpatory, I find it even more damning:
http://independentpoliticalreport.com/2016/02/gary-johnson-responds-to-critics-on-nm-prison-privatization-says-public-employee-unions-are-bigger-opponents-of-reform/
And here's the relevant quote from Johnson, from the prior link:
Some who are concerned about private prisons have also suggested that, as Governor, I should have simply pulled out a pardon pen and released enough prisoners to solve the State’s prison crisis. Actually governing is very different than commenting. Yes, as in many states, the Governor of New Mexico has the authority to grant clemency and pardon. But also as in most states, there is an established process for doing so – and it is a lengthy and very structured system. The notion of simply turning hundreds of prisoners loose in order to immediately vacate cells was not a real-world option – and I operate in the real world.
So, he had the power to do right, but rather than "doing right," his respect for the illegitimate system caused him to do wrong. (Both anarchist and minarchist formulations of libertarianism hold that not using one's full political power to prevent unjust punishment is morally wrong. Why respect a totalitarian legislature? No reason given. Johnson won't answer probing philosophical questions.)
In my opinion, the prior examples of "lack of commitment to individual freedom" and "lack of understanding of what individual freedom even means" disqualify Johnson as a "standard bearer" for the Libertarian Party. He had read "Atlas Shrugged," but there was no indication he had read Thoreau's "Resistance to Civil Government" or Bastiat's "The Law," or anything more complex. Nor that he understands the concepts therein.
The designers of the wonderful website "Republican Lite" got it right.
In 2012, Gary Johnson accepted a former judge who had publicly stated that he disagreed with jury nullification of law as his running mate. This was beyond the pale, and completely unacceptable, especially because libertarian judges like John Buttrick and Susan Bell actually inform the jury of their right to "nullify" unjust laws, or "vote their conscience, even if it directly disagrees with the law." In 2016, he chose former prosecutor and CFR (Council on Foreign Relations) board member, and former governor of Massachusetts, William Weld (who famously said he "vouched for" the character of Hillary Clinton).
...None of the prior anti-liberty stances or actions were problems for Gary Johnson, because he believes that the number of aggregates supporting a position or action can make wrong positions or actions into "acceptable" ones. My belief: This position is "insufficiently radical to produce valuable change toward individual liberty."
To be credible, the Libertarian Party must run radical, philosophically-aware, voluntaryist candidates like Harry Browne who believe that the government's only legitimate function(as described in Bastiat's "The Law") is collectivizing "only the same retaliatory force that every individual has a right to pursue on his/her own" and the "due process"(the right to habeas corpus; the right to trial by a randomly-selected, independent jury; a public trial; a speedy trial, ) necessary to make sure that that force is properly and fairly collectivized, and that all individuals in society have exactly the same rights and legal powers.
This is why John McAfee or Doug Casey can legitimately run as Libertarians, but someone like Gary Johnson or Bob Barr should not be allowed to do so.
Gary Johnson and 2008 LP presidential candidate Bob Barr eschewed the company and advice of libertarians when they held power. When they did accept the advice of libertarians, they went back on their word. Gary Johnson privatized prisons while the drug war was being waged and while hundreds of peaceful, safely-driving motorists were extorted for exceeding arbitrary speed limits in New Mexico. As explored above, Johnson failed to pardon Libertarian activists for unjust "electioneering" convictions. Bob Barr continued to maintain that the USA should help Alvaro Uribe wage his drug war in Columbia with taxpayer dollars, even after he became the 2008 Libertarian Party nominee.
As local colonies reject prohibitionist tyrannies worldwide, the USA Libertarian Party needs to be a shining example of classical liberalism, rather than a "Republican Lite" backwater.