After nearly two weeks of testimony from about a dozen witnesses for the prosecution in the federal extortion trial of Kenneth Brissette and Timothy Sullivan, lawyers for the defense called only two witnesses to the stand before resting their case, including former Boston Police Commissioner Bill Evans.

Evans' testimony, as well as the testimony of the defense's other witness, may have proved formidable in bolstering the defense's chief arguments throughout the trial: that the defendants had nothing to do with problems the Boston Calling music festival was having obtaining crucial permits in 2014; and that there is no evidence the defendants attempted to interfere with the festival's opening after meeting with festival representatives to discuss their hiring union labor.

Prosecutors allege that Brissette and Sullivan illegally pressured Boston Calling into hiring union stagehands in order to please their pro-union boss, Boston Mayor Marty Walsh; and that the men used the festival was facing ruin if it didn't obtain crucial permits as leverage over the festival's executives.

But on the stand, former BPD Commissioner Evans forcefully denied that delays in the festival's liquor license had anything to do with either defendant -- and forcefully asserted that, on the contrary,he himself, along with senior BPD staff, had raised serious concerns over the festival's liquor license and what Evans called serious public safety issues associated with previous Boston Calling festivals.

Evans, who testified via pre-recorded video due to a running injury, testified that the local police captain had relayed concerns over intoxication, underage drinking, and a reputed sexual assault at the concert's prior, May 2014 festival.

"He said we have to get better control over this event," Evans testified.

Evans said he did not want to prevent the festival from opening -- but was not about to back down on his concerns over Boston Calling's liquor license and his objection to the festival's request for 11 hours per day of alcohol sales.

"The more hours" of sales you have, Evans testified, "the more drinking you're going to have. ... I have a very firm bracket on alcohol. I have a reputation to maintain out there."

"All I knew was we had problems in May and I didn't want to have them in September," Evans said.

Evans testified to meeting with Boston Calling's CEO and director, Brian Appel and Mike Snow, who testified for the prosecution earlier in the trial, to express his concerns.

The festival's executives "felt entitled," Evans recalled, " .. but I held firm."

Perhaps most critical to the defense's case, Evans was equally forceful in denying that the defendants played any role in his intervention around the festival's liquor license.

"With regard to the liquor license we're talking about, do you recall whether you had any conversation at all with Kenneth Brissette about whether those liquor licenses should or should not be approved?" asked Brissette attorney Bill Kettlewell.

"Never once," Evans answered.

"Do you recall concerns with unions?" around the event, Kettlewell asked.

"I never had anything to do with that," Evans said. "I never had any clue who they were hiring or weren't hiring. I was concerned soely with public safety."

Asked by attorney Thomas Kiley, representing defendant Sullivan, whether Evans had ever spoken to Sullivan about the festival's permits, Evans was unequivocal.

"I didn't know who Tim Sullivan was," Evans answered.

Also testifying for the defense was Patricia Malone, formerly in charge of issuing entertainment licenses for the City of Boston.

Malone agreed on the stand that she signed Boston Calling's entertainment license just days before the festival was to open, but testified that that was not unusual -- and that the defendants did not and could not have caused her to delay the permit at their request.

During cross-examination, prosecutors attempted to poke holes in that testimony.

"Is it fair to say that in 2014 it was possible for the heads of different departments, including Kenneth Brissette, to call you to stop an event from getting a license?" asked U.S. Attorney Laura Kaplan.

"No, it was not," Malone answered.

The jury will hear closing argument Tuesday.

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