Free from the restraints of sitting in a partisan caucus, newly-appointed senators who identify as Independents are struggling with just how independent they should really be, and how far they should go in opposing the Liberal government's agenda, according to a memo obtained by CBC News.

Independent Quebec Sen. Marc Gold, who serves in a leadership role as the caucus "liaison," has sent a document to his colleagues in the Independent Senators Group (ISG) — many of whom are political neophytes with little past legislative experience — explaining how he believes his colleagues should balance their role as legislators in a chamber designed to be "complementary" to the House of Commons with their desire to live out the independence the Liberal government promised them when they were appointed.

"This is a real dilemma for us, as we do not represent the government and are committed to our Independence," Gold writes.

I've got a position in the Senate given to me by Prime Minister Trudeau to be an independent and that is what I am going to be. - Sen. David Adams Richards

In a section on "self-restraint" and "deference," however, Gold urges senators to avoid defeating government legislation that enacts an election promise, thus adhering to the so-called "Salisbury Convention" that legislators in U.K.'s House of Lords follow when debating bills.

It's an argument that echoes one recently made by the government's representative in the upper house, Peter Harder, in a discussion paper that urges restraint when dealing with government business. "The credibility of Senate ... depends on a measured and judicious approach to its relationship with the other place," Harder writes.

'Uncomfortable and unavoidable truth'

While Gold notes ISG members are not forced to show up to vote and are not held to account for missing sittings of the Senate — as was the common practice in the partisan caucuses — the ISG "bears a responsibility for how government bills are handled in the Senate."

"This leads to an uncomfortable and unavoidable truth. If government bills are defeated because the ISG cannot muster the votes to support them, the critics of the new appointment process will conclude that the experiment was a failure. This would have the effect of delegitimizing the modernization project of creating a more effective, independent and less partisan Senate," Gold writes.

So far, the Liberal government has depended on Independent senators — who now hold a plurality of seats in the Senate — to serve as their foot soldiers and help pass bills in the face of entrenched opposition from Conservative senators.

'I'd rather be on my own'

The letter comes at a time of growing pains for the ISG, which just lost a member of its fledgling caucus: New Brunswick Sen. David Adams Richards.

In an interview with CBC News, Richards said he left the ISG to sit as a "non-affiliated" because he says he would feel more "comfortable doing things alone as I've always done. I'm just going to sit as a solitary independent."

Richards said Trudeau promised him complete independence when he was named to the upper house.

"I don't think anyone put put any pressure on me to vote ... but it's a fairly large group and I'd rather be on my own," Richards said of the ISG. "I've got a position in the Senate given to me by Prime Minister Trudeau to be an independent and that is what I am going to be."

The Gold memo was written after the government avoided a potentially embarrassing defeat on its cannabis legislation: Independent senators travelling with committees were asked to come back to Ottawa at the last moment to prop up the bill in the face of Tory opposition. Every member of the ISG, except for P.E.I. Sen. Mike Duffy, fell in line, voting to send the bill to committee for further study.

The government's effort to mobilize ISG senators prompted accusations that the Independent label is a bit of a farce.

The Independents have voted largely in lockstep with the government's Senate leadership team, but they haven't shied away from proposing a flurry of amendments to government bills on everything from immigration to diversity on boards, changes to transport regulations and the definition of a status Indian, among others.

Recently, the Senate's transport committee approved, with support from Independent, Liberal and Conservative members alike, an unusually large number of amendments — 18 — to the government's omnibus transportation legislation, C-49.

Gold said that while there are grey areas, generally senators should not "give priority to our values and policy preferences" when voting or considering an amendment.

"Every piece of legislation needs to be assessed on its merits, and independent senators may very well disagree about the scope of their role. But our independence to vote or amend as we choose is not unlimited," Gold writes.

"We were not summoned to the Senate to substitute our policy preferences for those of the elected House of Commons. This would be inconsistent with our role as a complimentary legislative body," he writes. "Nor were we summoned to give free [rein] to the causes we champion, however virtuous they may be."