A CBC examination of federal Liberal Party documents released Monday reveals that key details are still missing, eight months after the party announced it would make its travel expenses transparent, as it began a release of travel claims by senators who were formerly part of its caucus.

The disclosure does not include travel costs incurred by spouses — who are permitted to travel business class to Ottawa with senators at public expense — and provides less overall information than what was previously issued by Conservative senators.

Ex-Liberal Senators' travel claims The Liberal Party began a release of details on Monday about its former senators' travel expenses. Click here to see the data.

Liberal Leader Justin Trudeau announced his party's "Open Parliament" plan for MPs and senators last June, which pledged "quarterly online expense reports that are easily accessible by Canadians."

The information on senators released Monday is tucked away on the Liberal Party website on a page titled "Senators who were formerly members of the National Liberal Caucus."

The expenses made public include travel costs for the former Liberal senators, per diem claims for meals while in Ottawa and some hospitality expenses. The data covers a period from last September until Dec. 31.

Conservative senators started posting their travel costs, including for their spouses, online last fall. Liberal MP John McCallum said his party chose not to post spousal expense claims because "we decided to do what the ministers currently do, which is to release MP travel and hospitality." He added that the party will eventually post those spousal costs.

5 senators claim more than $10,000

A review of the expenses that were made public Monday shows that several then-Liberal senators each incurred thousands of dollars in travel costs between Oct. 14 and Nov. 22. There is no suggestion that these expenses did not fall within Senate guidelines.

Nova Scotia Senator Wilfred Moore claimed over $15,000 in travel and meal expenses during the period. Included in his expenses was a bill in late October of just over $3,300 in travel for one return trip from Chester, N.S., to Ottawa.

Moore told CBC News he was surprised that he was among the highest spenders and that he tried hard to keep his travel expenses down. He said the high tally might have been due to an unexpected extra trip he made to Ottawa for a Senate sitting.

At least five members of the then-Liberal Senate caucus each claimed over $10,000 in travel costs during the five-week period.

All members of the Senate, who earn a base salary of $135,200 annually, are limited to a certain number of reimbursed flights per year, but there is no restriction on travelling business class or on the amount they can spend on any specific flight.

While the Senate already publishes quarterly summaries of office, travel, living and hospitality expenses for each senator, these reports don't reveal any specific costs, just the total for each three-month period.

Earlier this month, a CBC News review of that information showed that some Tory Senators routinely billed the public to bring their spouses to Ottawa. Alberta Senator Scott Tannas claimed more than $12,000 in airfare and hotel costs for himself and his wife for a two-day trip last fall. In an interview with CBC, the newly appointed senator apologized for the amount of the travel claim.

“Those numbers will come down substantially. Some of that by virtue of just gaining experience here and knowing how to manage travel better,” Tannas said.

Since the CBC review of the Conservative expense claims, the party's senators have released even more expense data, covering up until Dec. 31.

The Liberals' new system of proactive voluntary disclosure was supposed to take effect last fall. At the time, expenses for a two-week period were made public online, but then removed, after Trudeau expelled all Liberal senators from the party caucus last month.

If you have any tips on this story, or other expense claim stories, please email investigations@cbc.ca or call 416-205-6575.